It’s a question I’ve heard in the past people ask each other as if it’s a competition as to who has the most (I currently have over 4500 in my tree and have gone back to the late 1500’s and my 10 times great grandfather). Everyone has different numbers of ancestors and it also depends on who you include in your tree.
So let’s break down the number of ancestors you have by generation.
Generation 1: 2 parents
Generation 2: 4 grandparents
Generation 3: 8 great grandparents
Generation 4: 16 great great grandparents
Generation 5: 32 great great great grandparents
Generation 6: 64 great great great great grandparents
Generation 7: 128 great great great great great grandparents
Generation 8: 256 great great great great great great grandparents
Generation 9: 512 great great great great great great great grandparents
Generation 10: 1024 great great great great great great great great grandparents
So if you consider a generation is usually 30 years 10 generations back will take you back 300 years and give you 2046 ancestors. If you take it back to 20 generations or 600 years you’d have 2,097,150 ancestors. Back 30 generations or 900 years (i.e. back to the year 1117) and you have 10,73,741,824. That’s just mind blowing. How can anyone have that many that many ancestors but of course we all have. Sort of. You have to consider that you could have duplicate ancestors due to lines of consanguinity (we’ll consider this later). So it’s not unrealistic that some of your ancestors were related when they married. Even if it is distantly, they could share however many times great grandparents. If you think about it unlike now people didn’t move much away from where they were born. So there was always a chance that the person they married shared ancestors with them. I’m not saying they married a close family member, but maybe a distant cousin, although you are still able to marry your cousin to this day.
OK so what is consanguinity? Well in basic terms it’s the relationship between family members. So the consanguinity between you and your parents is one degree, for a 3 times great grandparent it is 5 degrees.
This has caused problems in the past and has also solved many a problem for an unhappy couple (or one half of a couple).
Let’s consider the problems to close consanguinity. Well it’s mainly helps genetic disorders spread. If you consider the marriage of King Philip II of Spain this highlights the problem. Philip was the great grandson of the Holy Roman Emperor Maximilliam I. In 1570 he married his niece Anna of Austria, the great great granddaughter of the Holy Roman Emperor Maximillian I. The couple had several children who did not survive childhood. Their only surviving child became King Philip III of Spain. Now Emperor Maximillian is thought to be the start of what is known as the Hapsburg (the family name) Jaw. This was a deformity that caused a wide long jaw and is known to cause pain. As Philip and Anna were so closely related the genetic deformity was in both of their DNA and passed to their son Philip III of Spain. He in turn married his 1st cousin once removed Margaret of Austria and their son, Phillip IV of Spain, married his niece (the daughter of his father’s sister Maria Anna of Spain and her husband Holy Roman Emperor Ferdinand III). This means that the genetic deformity kept spreading and so by the time Philip IV son Charles II was born his deformity was so bad he had trouble eating and he had mental problems and this was just in 6 generations.
So to solving the problems, King Henry VIII of England used it to his benefit.
Henry used consanguinity as a reason for his divorce and annulment from his first 2 wives. In 1509 Henry married Catherine of Aragon the widow of his brother Arthur. By 1533 Henry was determined to marry his long-time mistress Anne Boleyn. He used the fact that Catherine was his former sister in law to claim consanguinity as thus void the marriage. He then used consanguinity again in 1536 to get out of his marriage to Anne Boleyn on the ground her sister Mary was his mistress for many years before Anne to that role. Neither ended well for his wives. Catherine died in poverty isolated from her family and friends and Anne died at the end of a war sword.
So when you start thinking you haven’t got enough people in your tree, it doesn’t matter. You may have less direct ancestors and remember if one of your ancestors is illegitimate this removes possibly hundred from your tree. But it doesn’t matter. Their your ancestors and important to you.