Short answers, pulled from the story.
The Theosophical Society was established on the 17th of November 1875 in New York City. Helena Petrovna Blavatsky, Colonel Henry Steel Olcott, William Quan Judge, and sixteen others gathered to declare their intent to form an unsectarian body dedicated to seeking truth.
Helena Blavatsky published The Secret Doctrine in 1888 to outline the belief in Intelligent Evolution of All Existence affecting every part of the known universe. The society teaches that reincarnation follows bodily death through a system of karma while human life aims for spiritual emancipation rather than material gain.
Colonel Henry Steel Olcott served as the first president until his death in 1907. Helena Blavatsky died in 1891 which triggered immediate internal conflict among surviving leaders including Annie Besant and William Quan Judge.
William Quan Judge left the main group in 1895 taking most American members with him to form a branch headquartered in Pasadena California. Rudolf Steiner became general secretary of the German-Austrian division in 1902 before breaking away in 1913 to form the Anthroposophical Society.
The society established branches in Madrid, Barcelona, Seville, Valencia, Alicante, Cádiz, and Dharma by 1921. A Spanish charter signed in 1921 created local groups across those locations while the Dublin organization claims direct receipt of its charter from Helena Blavatsky itself.