This list shows the most senior line of descent of Elizabeth II from William I of England. Each person on the list is the son or daughter of the person above him or her on the list. There are many other more junior lines of descent of the family, but the crown in theory at least only descends through the most senior line. Due to extinct lines, large parts of entire royal houses (Lancaster, Tudor, Stuart) are bypassed in the current most senior line. The numbers can be used to calculate the number of generations between two individuals on this list.
The senior direct royal line
18 monarchs of England, Great Britain, or United Kingdom are in the senior direct line, and two who were King or Queen of Scots.