Short answers, pulled from the story.
The earliest records of vegetarianism as a concept and practice among a significant number of people come from ancient India, especially among Hindus and Jains. Jain and Buddhist sources trace the principle of nonviolence toward animals to the 6th century BCE, with Lord Parshvanath, the 23rd Jain leader, said to have preached nonviolence as far back as the 9th century BCE.
Pythagoras believed that animals possess both intelligence and passion, the critical elements for sentience, making their mistreatment unethical. His followers also connected the avoidance of meat to the concept of transmigration of the soul, metempsychosis, and strict Pythagoreans additionally avoided eggs and refused the ritual offering of meat to the gods. Before the word 'vegetarianism' was coined, English speakers called vegetarians 'Pythagoreans.'
The first Vegetarian Society of the modern Western world was founded in England in 1847 by 140 participants at a conference in Ramsgate. By 1853 the Society had 889 members, and by the end of the century it had attracted nearly 4,000.
Donald Watson, secretary of the Leicester branch of the British Vegetarian Society, coined the word vegan in November 1944 when he launched a new quarterly newsletter called The Vegan News. Watson and co-founder Dorothy Morgan chose the word by taking the first three and last two letters of 'vegetarian,' because it marked, in Watson's words, 'the beginning and end of vegetarian.'
Women were central to the Victorian vegetarian movement's practical work. Of the 26 vegetarian cookbooks published during the Victorian era, 14 were written by women. In 1895, Alexandrine Veigele founded the Women's Vegetarian Union in London to promote a simpler diet and reach the working class, and prominent figures including Frances Power Cobbe and Charlotte Perkins Gilman linked vegetarianism to feminism.
Indian vegetarians, who are primarily lacto-vegetarians, are estimated to make up more than 70 percent of the world's vegetarians. They represent between 20 and 42 percent of India's population, though a study by anthropologist Balmurli Natrajan and economist Suraj Jacob puts the figure at approximately 20 percent. In the United States, surveys have found roughly 6 percent of adults never eat meat, poultry, or fish.