Electrum was created by Thomas Voegtlin in November 2011.
Holy shit, that's
really early. I thought it started in 2013.
I used to think it started just after that bipwas released in 2015...
It was the main implementation before it was possible to rpc into bitcoin full nodes... I'm surprised they started on python2, python3 was out by that time as I started learning it that year...