Complex sentence: According to Father Mariana, Leon left Castile for France after the death of his protector in 1390, served as French ambassador to England in 1389 and in 1392 and died in Paris, where he was buried.
Split into simpler sentences: According to Father Mariana, Leon left Castile for France after the death of his protector in 1390. Mutafian, "Leon V" Leon continued diplomatic mission to England in 1389 and in 1392 and died in Paris, where he was buried.