From what I understand. Ireland is greatly considered to be a chief export of potatoes, and the whole deal of the great potato famine. The thing is I also remember reading that things like potatoes, tomatoes etc where discovered on the first time in the new world. So how did irelands economy and culture shift so drastically to make to potato famine possible. Or am I just 100% wrong in this whole chapter of history?
Ireland has never been a rich country, with generally poor growing land for crops. Much of Ireland was used for grazing, but animals dont have high food yield over time compared to crops. What farmland Ireland did have was used mostly for food export, as opposed to local consumption, at least that was the case under British rule of Ireland.
For a long time Ireland was sparsely populated, and it was only with the discovery of potatoes that they could grow enough food to allow for significant population growth, as potatoes could grow on harsh terrain that was unsuitable for other crops such as wheat or barley.
So by the time that the potato famine occurred the Irish population was eating potato as their primary food crop, and had little to fall back on as there was not much food stored due to wheat being an export. The famine could have had its impact reduced if the British government had handled the situation better, but they made poor judgement which led to more starvation. Specifically that the British had continued to export Irish wheat.
Also to respond to a statement you made in your post, Ireland does not export potatoes in any significant capacity, because as mentioned previously they are grown for domestic consumption.
For this you need to look at three things
A) who owns the land
B) who gains from production on said land
C) who produces on the land and how do they feed themselves
So A&B is easy - the land was mainly owned by English nobility who wanted to produce clash crops on the land they owned. Sadly they needed people for that - the Irish - and the Irish needed to eat.
So now some land had to be left over to grow food for said Irish. So to maximize profit a food source which is very energy dense is best - since more bang (food) for the buck - and here the potato comes into play - it is simply more nutrious then any other form of cereal , it's cheap to grow and doesn't need much care - plus wheat and so on could be sold to England so why feed it to those pesky Irish. (Even during the Irish famine Irland exported huge amounts of food to England)
And there is how the dependence happend - Potatoes were the food for the Irish, everything else was sold and since the Irish were too damn poor to afford any other food they died.
This is a side question to OP's if anybody happens to have an answer, but why didn't the Irish just fish? Is there something I'm missing about the waters around Ireland?