The duke had played power politics with the young Emperor several years earlier in his reign .
Was demonstrably ruthless ( kidnapping and forcing the marriage to Emperor 's sister ) even without the support of the other princes of the Kingdom of Germany .
The duke had played power politics with the young Emperor several years earlier in his reign , and was demonstrably ruthless ( kidnapping and forcing the marriage to Henry 's sister ) even without the support of the other princes of the Kingdom of Germany .