Can the Queen trace her ancestors to William I?
Certainly. Keep in mind that there is so much crossover in the lines (read: inbreeding) that Elizabeth (or Victoria, if that’s specifically who you’re asking about) can trace her ancestry to just about any royal figure from European history. Here’s just one lineage, and certainly not the only one: Queen Elizabeth Alexandra Mary Windsor II (1926- ) King George Albert Windsor VI (1895-1952) King George Windsor V (1865-1936) King Edward Wettin VII (1841-1910) Queen Victoria Hanover (1819-1901) Prince Edward Augustus Hanover (1767-1820) King George Hanover III (1738-1820) Prince Frederick Louis Hanover (1707-1751) King George Augustus Hanover II (1683-1760) King George Louis Hanover I (1660-1727) Countess Sophia Hanover (1630-1714) Princess Elizabeth Stuart (1596-1662) King James Stuart VI/I (1566-1625) Mary Stuart I, Queen of Scots (1542-1587) King James Stuart V (1512-1542) Margaret Tudor (1489-1541) Elizabeth York (1466-1503) King Edward York IV (1442-1483) Duke Richard York (1411-1460)