the bulk of the deaths recorded by the Nuns were in 1944-1946. Was there a reason for this? Was there something happening in Ireland that would have made this more likely?
In the late 1940s, like the rest of Western Europe, Ireland suffered economically, because all of it's major pre-war trading partners were them selves economically devestated and had little surplus to trade with Ireland. Additonally, Tuam is in Galway, which is still one of the poorer and less developed regions in Ireland. Most of the industry in Ireland was, and is, located on the cities of the Eastern Coast. Additionally, until the 1950s, the government of the Republic of Ireland tried to implement a form a economic nationalism with high tarriff barriers to encourage import substituion. This failed miserably; all it succeeded in doing is to manage to hurt the Irish economy at a time when the rest of Western Europe was growing at a rapid clip. Ireland continued to one of the poorest conuntries in Wester Europe, right up until the late 1960s. During the 1950s, most other states in Western Europe were attracting economic migrants from the 3rd world, and had growing economies and populations. In contrast. Ireland's economic grown barely kept up with inflation, and Ireland actually suffered net population loss of about 400,00 persons, which is rather a lot considering that in this period the total labor force with formal employment never exceeded 1.2 million persons. It was not until the 1970s that Ireland began to catch up with the rest of Europe economically and demographically, and even then, per-capita GDP (measured using PPP, no less) in Ireland continued to trail that of it's neighbors. Ireland continued to have high unployment, public employment exceeding 1/3rd of the labor force, and a NET population loss of 1% ANNUALLY, all right up until the beginning of the "Celtic Tiger" boom in 1995.
TL;DR: For a whole bunch of reasons, the Irish Republic's economy was really underperforming right up into the 1990s. One of the problems that unwed mothers faced in ireland, aside from social stigma, was that because the irish economy sucked so bad, it was literally impossible to survive as a single mother without help form family or the church -- you would actually starve to death, if it weren't for church charity, which came with it's own set of strings attached.
Do you have a link discussing this event? I don't have even the faintest idea what you're talking about
In regards to question 2, there seems to have been a suggestion that it was a famine grave. There are quite a lot of mass graves dating from that era, although I wouldn't call it common to find one. The home was a workhouse before it became a mother and baby home, so a mass grave wouldn't have been a huge surprise.
For question 3, you are somewhat violating the 20 year rule on this sub, as it does concern events that have more or less occurred over the last few years. We don't know how many are actually there. The 800 figure comes from a local historian who has researched this topic, and come up with about 796 death certificates. There are conflicting reports about this. Its being said that only some are actually in the septic tank (about 20) with the rest in an unofficial graveyard. Again, this seems to be a bit up in the air at the moment, so it's probably too early to say for sure. Wait for the inquiry.