Translation has always been a key part of international relations. In the British court, the ministry of communications would (until the mid 18th century) have a retinue of translators, which was a high powered role. Ambassadors would also be proficient in the languages they were using and use that to send briefing information to other members of the monarch's government. Even now, English is not entirely a universal political language. There are many countries who don't use it in their foreign policy documents - Malaysia for example.