 His paternal uncle Anders Lennartsson was Lord High Constable of Sweden and trusted by Duke Charles, but he fell at the Battle of Kircholm in 1605.At the age of fifteen he became one of the pages of the young King Gustavus Adolphus and was allowed to observe the Livonian War, such as the conquest of Riga in 1621.At the age of twenty, he made his grand tour, getting to know foreign countries.