Complex sentence: Coverdale did not immediately return to England, although the prospects for reformers looked better, but in March 1548 he wrote to John Calvin that he was now returning, after eight years of exile for his faith.
Split into simpler sentences: Coverdale did not immediately return to England, although the prospects looked better for him. However in March 1548 he wrote to John Calvin that he was now returning, after eight years of exile for his faith.