Daily Mail:

Is the mystery disappearance of Swedish count who had an affair with King George I’s wife about to be solved?

The mysterious disappearance of a Swedish count reputed to have had an affair with the wife of George Ludwig of Hannover, later King George I of Great Britain, may soon be solved.

German authorities are planning to test DNA taken from human remains found beneath the Leine Palace in Hannover earlier this month to determine whether they belong to Count Philipp Christoph von Koenigsmarck.

Hannover prosecutor Thomas Klinge told the DPA news agency today that if the DNA did prove to be Koenigsmarck it was highly likely he was murdered when he vanished without a trace on July 1, 1694.
more at link

Wikipedia: Philip Christoph von Königsmarck