Short answers, pulled from the story.
Roerichism is a spiritual, cultural, and social movement centered on the teaching of Agni Yoga, also called Living Ethics, transmitted by Helena and Nicholas Roerich. It emerged in the United States in the first half of the twentieth century but has been described as a thoroughly Russian new religious movement due to its deep connections with Russia and Russian cosmism.
Agni Yoga is a religious doctrine transmitted by Helena and Nicholas Roerich from 1920, drawing on Theosophy, Vedic and Buddhist traditions, and both Eastern and Western religions. Unlike traditional yogas focused on physical disciplines or meditation, Agni Yoga is a path practiced in daily life, emphasizing the yoga of fiery energy, consciousness, and directed thought. Its followers believe thought is a form of energy capable of affecting the entire planet.
Helena Roerich (1879-1955) was a Russian theosophist, writer, and public figure who developed the philosophical teaching of Living Ethics. She published fourteen volumes of the Agni Yoga series, placing no author's name on those volumes, and acknowledged authorship of only three books under pen-names: "The Foundations of Buddhism" (1927), "The Cryptograms of the East" (1929), and "The Banner of the Reverent Sergius" (1934). Two volumes of her letters were published in Riga in 1940.
The Roerich Pact was an international treaty initiated by Nicholas Roerich to protect cultural values during both wartime and peacetime, modeled on the Red Cross's protection of hospitals. President Franklin D. Roosevelt ratified it on the 25th of October 1935, with Secretary of State Cordell Hull countersigning. Albert Einstein and Rabindranath Tagore were among the international figures who joined the effort.
The Nicholas Roerich Museum is located in a brownstone at 319 West 107th Street on Manhattan's Upper West Side in New York City. It holds between 100 and 200 of Roerich's works as well as archival materials, and is the largest center of Roerich-related activity outside of Russia.
Organizations based on Roerichism's ideas continued to form after all members of the Roerich family had died. The World Organisation of Culture of Health was founded in 1994 with Victor Skumin as president-founder, connecting health to culture through the framework of Agni Yoga. The International Center of the Roerichs in Russia became an associated member of the Non-Governmental Organizations Association under the United Nations Department of Public Information.