This question came to me out of no where one day. It’s simple, but brings up some interesting ideas. Obviously at one point there would have been just a handful of countries, but over time more and more were created. In modern history, when did the number of countries peak? Has the number risen and fallen? Has it steadily grown?
I wrote a python script to grab the data from these pages. Then for the years after 1960, I used this Wikipedia list to add and subtract countries for each year.
Plotting the data led to this interesting chart. I made some annotations of key points that led to a steep increase or decrease.
The most obvious problem with this is who defines what a nation is? Many nations are not recognized immediately and even today different nations choose to not recognize other nations. Additionally, the lists on Wikipedia are almost certainly incomplete. Nonetheless, I feel the numbers are at least reasonably accurate and point out some interesting periods in world history.