Complex sentence: The last Dunkeld king, Alexander III, died in 1286 leaving only a single infant granddaughter as heir; four years later, Margaret, Maid of Norway herself died in a tragic shipwreck "en route" to Scotland.
Split into simpler sentences: The last Dunkeld king, Alexander III, died leaving only a single infant granddaughter as heir. When Margaret, Maid of Norway herself died in a tragic shipwreck "en route" to Scotland.