Complex sentence: Dorothea was given very large estates in Sweden at her first wedding, which she lost controll over in 1464, and the rest of her life, she faught to regain controll over them, and also asked for the help of the Pope.
Split into simpler sentences: Dorothea was given very large estates in Sweden at her first wedding, which she lost control over in 1464. For the rest of her life, she fought to regain control over them, and also asked for the help of the Pope.