Complex sentence: While mortally wounded, he remained in command of his ship--for "conspicuous devotion to duty, extraordinary courage, and complete disregard of his own life", he posthumously received the Medal of Honor.
Split into simpler sentences: While mortally wounded, he remained in command of his ship. For "conspicuous devotion to duty, extraordinary courage, and complete disregard of his own life," he posthumously received the Medal of Honor.