Updated 6 Mar 2025

Acronyms and Terms:
ybp = years before present (2024 CE)
AD = CE = Common Era = Year 1 and after
BC = BCE = before Common Era or before Year 1

Haplogroup - A genetic population group of people who share a common ancestor on either their paternal or maternal line, e.g. paternal haplogroup I-BY172565. Y-DNA (paternal side) and mtDNA (maternal size) change only by chance mutation at each generation (≈30 years)

Subclade - A subgroup of a haplogroup.

Formed - On the paternal side, when, by chance, a Y-DNA mutation generates a new haplogroup. For example, Haplogroup I-S2606 is a subclade of Haplogroup I-L38. Haplogroup L-L38 formed around 8200 BCE and I-S2606 became a subclade of I-L38, because of a chance mutation around 2700 BCE.

TMRCA - Time to Most Recent Common Ancestor: a measure of how long ago any two male individuals likely shared a common paternal ancestor.

Note: Locations (below) use today’s map names; in most cases the name simply identifies the general area or region where the ancient ancestor lived before written records or human documention existed (prehistory).

FTDNA - DNA analysis at familytreedna.com
YFULL - DNA analysis at yfull.com
aDNA - Ancient DNA

Major Events - Chronology in Reverse Order

1740 CE | Brothers John ca1712 Garrison and Aaron 1715 Garrison living in Stafford County, Virginia, identified in Overwharton Parish Record (1720-1760)

Shared Ancestor: We share a common paternal ancestor with Ellwangen 30 (named by burial location) who lived between 1486-1627 CE in the Historical Age (Ellwangen, Ostalbkreis District, Baden-Württemberg, Germany); our shared common ancestor lived ≈2750 BCE (I-L38)

Shared Ancestor: We share a common paternal ancestor with Austin Friary 522 (named by burial location) who lived between 1200-1540 CE in Medieval Britain (Augustinian Friars, Cambridgeshire, England); our shared common ancestor lived ≈2750 BCE (I-L38)

1085 CE | Introduction of family surnames generally attributed to William the Conqueror’s Domesday Book identifying the King’s holdings and his subjects for taxation.

1066 CE | William II, Duke of Normandy, invaded England and conquered the resident Anglo-Saxons, becoming “William the Conquerer”.

1016-1042 CE | Danish Kings of England
871-899 CE | English Anglo-Saxon King Alfred the Great
793-900 CE | Viking Invasions of England

Shared Ancestor: We share a common paternal ancestor with Heslerton 20641 (named by burial location) who lived between 450-650 CE in Medieval Britain (West Heslerton, Yorkshire, England); our shared common ancestor lived ≈2300 BCE (I-FGC29569; Essex County, England)

Shared Ancestor: We share a common paternal ancestor with Buckland 24 (named by burial location) who lived between 400-800 CE in Medieval Britain (Dover Buckland, Kent, England); our shared common ancestor lived ≈2700 BCE (I-L38; Suffolk, England)

YDNA Haplogroup Formation - Chronology in Reverse Order

Our ancient ancestors, living in a time before surnames existed, were part of the Jastorf culture (described futher on). They lived in the Hamburg (Iron Age), Germany region around 250 CE until becoming part of the developing southern (Danish) Viking culture after 800 CE.

350-570 CE | Large-Scale European Tribal Migration Period; invasions and settlements by Agles, Saxons, Jutes, Franks, Goths, Huns, Vandels, Gaels, etc.

I-BY172565 ≈1650 England | Our Garrison “signature” haplogroup. See “Top Garrison” Person Sheet Notes for Danish Viking-Norman (Normandy, France) origins. | Identified Descendants: 1740 CE, Stafford County, Virginia

Per FTDNA: “There is not enough user-reported geographical information to estimate the ancestral location of your most specific haplogroup, I-BY172565.” I-BY172565 is a subclade of Haplogroup I-FT66718 (below); however, there is an approximate 1100 year gap between I-FT66718 and I-BY172565 which may reflect one or more haplogroups that haven’t been identified yet.

I-FT66718 550 CE Denmark - Lolland Island

⬆ Beginning of Common Era - CE ⬆

⬇ Before Common Era - BCE ⬇

I-BY86358 50 BCE Sweden - Halland, northern coast

Shared Ancestor: We share a common paternal ancestor with Gurgy 32 (named by burial location) who lived between 300 - 100 BCE during the European Iron Age (Gurgy Les Noisats, Yonne, France); our shared common ancestor lived ≈2550 BCE (I-S2606).

500 BCE - 800 CE | The Iron Age in Scandinavia and Northern Europe began with the Jastorf Culture and is taken to last until the beginning Viking Age.

The various Germanic tribes (cultures and languages) started to exist in the Jastorf culture that developed out of the Nordic Bronze Age. The Jastorf culture extended from southern Sweden and Denmark in the north to the Harz Mountains (present day Germany) in the south, and from the Rhine River in the west to the Oder River in the east. The people of this culture were skilled in metalworking, and they created intricate metal objects like jewelry, weapons, and tools. They also made pottery, often with elaborate designs and decorations. The Jastorf people were excellent farmers and cattle herders, and they had developed a sophisticated system of agriculture and animal husbandry. The Jastorf people buried their dead in elaborate burial mounds, and these mounds often contained rich grave goods, such as weapons, jewelry, and pottery.

Shared Ancestor: We share a common paternal ancestor with Magdalenenburg 008 (named by burial location) who lived between 616 - 530 BCE during the Early Iron Age (Magdalenenberg, Villingen-Schwenningen, in Baden-Württemberg, Germany. Magdalenenberg is considered the largest tumulus (burial mound) from the Hallstatt D period (620-450 BCE) in Central Europe. Our shared common ancestor lived ≈2700 BCE (I-L38).

750-250 BCE | A North Sea Germanic people inhabited the northern part of the Netherlands (north of the Rhine River) and extending along the North Sea and into Jutland. This group is also sometimes referred to as the "Ingvaeones". Included in this group are the peoples who would later develop into early Saxons. This means that some of the North Sea germanic peoples migrated east to become part of the Jastorf Culture (early Saxons).

830s BCE | Danish Vikings began raiding in what is today France. These “Normans” or "north men" settled in northwest France controlling the region known as Normandy until the mid 13th century.

***I-Y51873*** 150 BCE England - East Riding of Yorkshire

Shared Ancestor: We share a common paternal ancestor with Rowbarrow 19859 (named by burial location) who lived between 1504 - 1403 BCE during the European Bronze Age (Rowbarrow, Wiltshire, England). Our shared common ancestor lived ≈8450 BCE (I-S2497).

I-FGC70154 1250 BCE England - Suffolk County, northeast coast

I-FGC70142 1550 BCE Germany - North Rhine-Westphalia (eastern border)

Shared Ancestor: We share a common paternal ancestor with Su Crucifissu Mannu 9 (named by burial location) who lived between 1867 - 1631 BCE during the Middle Bronze Age (Su Crucifissu Mannu, Porto Torres, Italy (Sardinia).). Our shared common ancestor lived ≈8450 BCE (I-S2497).

I-FGC68670 1700 BCE Germany - south central North Rhine-Westphalia

1750-500 BCE Nordic Bronze Age | Scandinavia and Northern Germany | People were skilled metalworkers and seafarers. They were expert traders, capable of running extensive trade networks. They were the ancestors of not only the Germanic tribes of the Migration Period, but also of the Vikings. This highly stratified society ruled by an aristocratic elite laid the foundation for much of what would become the Germanic peoples.

Shared Ancestors: Skeletal remains of 60 individuals archaeologically dated between 2000-1800 BCE in Lichtenstein Cave just south of Förste, Lower Saxony, Germany on the southwestern edge of the Harz Mountains (5 mi. east of Osterode). Initially assigned to Haplogroup I-P215 in 2016. Subsequently assigned to Haplogroup I-PH2591 in 2022.

Shared Ancestor: We share a common paternal ancestor with Esperstedt 2 (named by burial location) who lived between 2138-2010 BCE during the Early Bronze Age (Esperstedt Region, Saalekrels District, Saxony-Anhalt, Germany). Our shared common ancestor lived ≈2700 BCE (I-L38).

I-PH2591 1850 BCE Germany - North Rhine-Westphalia, Western Border

I-PH1237 2200 BCE England - Kent (off shore -7m)

I-FGC29569 2350 BCE England - Essex (off shore -7m)

I-FGC29656 2500 BCE England - Essex (off shore -9m)

I-S2606 2550 BCE England - Suffolk (off shore -9m).

2800-2300 BCE | The Battle Axe culture was the progenitor of the Germanic peoples. Upon their arrival to Scandinavia in around 2800 BCE, these peoples brought the distinct cultural aspects of the Indo-Europeans with them, as well as the Indo European language. Their battle axes are by far the most characteristic aspect of this culture, and its identifying trait. They are most often made from polished flint stone, skillfully worked in a precise, curved shape resembling a boat. The axe heads, even though they are made from stone, showcase an immense amount of artisanal skill. Upon their absorption of the native cultures, and their fusion with them, different cultural aspects were combined. This was a necessary component which helped push Scandinavia into the Nordic Bronze Age.

Shared Ancestor: We share a common paternal ancestor with Sramore 62 (named by burial location) who lived between 4226 - 3963 BCE during the Early Neolithic Age (Cave, Sramore, County Leitrim, Ireland). Our shared common ancestor lived ≈10000 BCE (I-S2519).

4300-2800 BCE | The Funnelbeaker culture emerged in northern modern-day Germany and is named for its characteristic ceramics, beakers and amphorae with funnel-shaped tops, which are found in dolmen burials.The Funnelbeaker people settled Scandinavia from the South, going from Germany to Denmark and the Southern parts of Norway and Sweden. Although they were largely of Early European Farmer (EEF) descent, people of the Funnelbeaker culture had a relatively high amount of hunter-gatherer admixture, particularly in Scandinavia. In terms of Y-DNA, current finds of DNA show that the men of the FBC culture mainly carried haplogroup I2, our Garrison Y-DNA branch origins.

Shared Ancestor: We share a common paternal ancestor with Henriksholm 747 (named by burial location) who lived between 4942 - 4613 BCE during the Late Mesolithic Age (Henriksholm-Bøgebakken (Vedbæk), Zealand, Denmark). Our shared common ancestor lived ≈8450 BCE (I-S2497).

5400-3950 BCE | The Ertebølle culture was a hunter-gatherer and fisher, pottery-making culture dating to the end of the Mesolithic period. The culture was concentrated in Southern Scandinavia. It is named after the type site, a location in the small village of Ertebølle on Limfjorden in Danish Jutland. The Ertebølle population settled on promontories, near or on beaches, on islands, and along rivers and estuaries away from the dense forests. Due to chance fluctuations in the sea level during Ertebølle occupation of the coast and subsequently, many of the culture sites are currently under 3m-4m of water.

6000-5200 BCE | The Kongemose, a mesolithic hunter-gatherer culture, is named after a location in western Zealand (Denmark) and its typical form is known from Denmark and Skåne (southern Sweden). The finds are characterised by long flintstone flakes, used for making characteristic rhombic arrowheads, scrapers, drills, awls, and toothed blades. Tiny micro blades constituted the edges of bone daggers that were often decorated with geometric patterns. Stone axes were made of a variety of stones, and other tools were made of horn and bone. The main economy was based on hunting red deer, roe deer, and wild boar, supplemented by fishing at the coastal settlements

I-L38 2750 BCE England - Suffolk (coastal)

Shared Ancestor: We share a common paternal ancestor with “Cheddar Man” (named by burial location) who lived between 8607-7982 BCE (Mesolithic era) in the western reaches of the island of Great Britain in an area known as Cheddar Gorge. Our shared common ancestor lived in East Sussex, England.

9000-4300 BCE | Mesolithic people occupied Britain by around 9,000 BC, and it has been occupied ever since. The Mesolithic culture varies between areas, but it is associated with a decline in the group hunting of large animals in favour of a broader hunter-gatherer way of life, and the development of more sophisticated and typically smaller lithic tools and weapons than the heavy-chipped equivalents typical of the Paleolithic. The more permanent settlements tend to be close to the sea or inland waters offering a good supply of food. Mesolithic societies are not seen as very complex, and burials are fairly simple.

I-S2497 8500 BCE England - East Sussex

I-S2519 10000 BCE England - Norfolk

I-S11321 10000 BCE England - Norfolk

I-S10728 14000 BCE Austria - Tirol

I-S2599 14000 BCE North Adriatic Sea (submerged)

I-P214 16000 BCE Northeast Italy | North Adriatic Sea (coastal, submerged)

I-L460 21000 BCE Southwestern Germany

aDNA | Haplogroup I-L460, commonly found in northern and central Europe is found in the early medieval population of England 400-1066 CE.

I-CTS2257 21000 BCE Southwestern Germany

(I2) I-P215 23000 BCE Southwestern Austria

I-M170 26000 BCE South East Austria

I-L758 33000 BCE Austria

I J-P124 40000 BCE South Eastern Iraq (border with Iran)