Complex sentence: After two and a half months of working on the Danish king, peregrine got him to offer to try to persuade the Spanish king to retire from the Low Countries and that Frederick would sent 2,000 horse to back up the English force already in the Netherlands.
Split into simpler sentences: After two and a half months of working on the Danish king, peregrine got him to offer to try to persuade the Spanish king to retire from the Low Countries. Frederick also agreed to send 2,000 horse to back up the English force already in the Netherlands.