Complex sentence: Even his closest friends were at first doubtful of his oath, but Gajah Mada kept pursuing his dream to unify Nusantara under the glory of Majapahit.
Split into simpler sentences: Even his closest friends were at first doubtful of his oath. But nonetheless, Gajahmada was serious in pursuing his dream to unify Nusantara under the glory of Majapahit.