It seems strange that many people think modern vegetarians and vegans are by accident meeting „the spirit of the time“. But the long history that has let to the present popularity is unknown even to many vegetarians and vegans themselves.
Up to the 19 century the vegetarians around the world refered themselves to as „Pythagoraens“. As you know Pythagoras lived some 500 years before Christ. He was one of the first prominent person to speak out for vegetarianism (it was the time of „isms“ then). Don’t forget about the long history of vegetarians in India. In the late 19th century then the Vegetarian Society came up. First in England, the US. then a short while later in other European countries like e.g. Germany, France, Italy, Switzerland and others. In 1908 on the 1. International Vegetarian World Congress in Dresden, Germany, the International Vegetarian Union (IVU) was founded. Some decades later Donald Watson „invented“ the expression „vegan“ for people who restrain from all animal products. That was in 1944. That is also the time when the „Vegan Society“ had its birth.
In all those centuries since Pythagoras there have been personalities who took a stance for the ethical movement of a plant based diet and lifestyle. Yes, it is a lifestyle but it is by no means just an episode. Hopefully more people learn about the rich past of the vegetarian movement and its culture.
Especially two sources are full of high quality content about all this: the Website of the IVU for its long history or you may visit the history page of IVU Vegfest. You find there biographies of many vegetarians who left an sustainable impact on history as IVU responsibles a.o.. People whose names you may never heard before, e.g.: Herr B. O. Dürr (Czechoslovakia), Oluf Egerod, Carl Gumprecht, Hans Feix, Yehudi Mehuin, Linda McCartney, George Bernard Shaw, Albert Schweitzer. You will find there informations about past events as congesses and others, about vegetarian history in India, in the US, in Europe, about special diets over the centuries and on and on.
Finally there is a fine and free e-book (over 200 pages) about the vegan history by John Davis who has been a long time head of the IVU.