My understanding of the page life cycle is as follows:
Given the above, where does the MasterPage's Load event fire? Google isn't helping as quite a lot of people say Load when talking about the OnLoad event.
Master Page load event is between Content page Load event and Master page controls Load event.
Check the MSDN for details
Although both Init and Load recursively occur on each control, they happen in reverse order. The Init event (and also the Unload event) for each child control occur before the corresponding event is raised for its container (bottom-up). However the Load event for a container occurs before the Load events for its child controls (top-down). Master pages behave like child controls on a page: the master page Init event occurs before the page Init and Load events, and the master page Load event occurs after the page Init and Load events.