 Complete the following phrase:  In August 1630, Anstruther served as ambassador to the Diet of Regensburg, and was kindly received by Ferdid II, Holy Roman Emperor. Although the Diet was dissolved, Anstruther managed to secure another meeting with Ferdid, before returning to Scandinavia, believing that any further work in the Holy Roman Empire would be prejudicial to Stuart interests. In 1631, after a sojourn to London, Anstruther returned to Hamburg. En route he visited The Hague to discuss new proposals offered by Charles I. These centered on trying to get the Duke of Bavaria elected as Emperor, and although the Dutch expressed reservations, Anstruther attended the Diet of Allied Princes at Heilbronn. In 1633, he attended another diet of Protestant princes and continued negotiating in Germany through April 1635. However, the Peace of Prague 1635 largely undermined Stuart interests in Germany, and in 1638 he turned down an appointment to represent Britain in a meeting with Christian IV in Hamburg. This may have been due to the signing of the National Covet and the outbreak of the 