Alternative history can be tackled in many ways. I choose time travel and multi verse as I believe in the possibility that for every event, action, decision, choice made (in many cases random or accidental), will have an infinitesimal number of alternatives. All these, will of course, create other choices down-the-line. My science fiction novel, 'The Tinners' Hut is one such example where cause and effect of a decision can have dire consequences without the perpetrator being aware; or even considering an eventual chaos. In this case, it's a king of England. His decreeing one event only to change it later, will cause havoc 300-years down his particular line that will affect the monarchy he is trying to defend.
If the man dies on the scaffold, his descendant will not be able to save the lives of 300 children being held in a 2008 hostage siege at a school in Bristol.