structural:reformatting, information:classification
Between the wars

In August 1920, Russell travelled to Soviet Russia as part of an official delegation sent by the British government to investigate the effects of the Russian Revolution. He wrote a four-part series of articles, titled "Soviet Russia—1920", for the magazine The Nation. He met Vladimir Lenin and had an hour-long conversation with him. In his autobiography, he mentions that he found Lenin disappointing, sensing an "impish cruelty" in him and comparing him to "an opinionated professor". He cruised down the Volga on a steamship. His experiences destroyed his previous tentative support for the revolution. He subsequently wrote a book, The Practice and Theory of Bolshevism, about his experiences on this trip, taken with a group of 24 others from the UK, all of whom came home thinking well of the Soviet regime, despite Russell's attempts to change their minds. For example, he told them that he had heard shots fired in the middle of the night and was sure that these were clandestine executions, but the others maintained that it was only cars backfiring.

Russell's lover Dora Black, a British author, feminist and socialist campaigner, visited Soviet Russia independently at the same time; in contrast to his reaction, she was enthusiastic about the Bolshevik revolution.

The following year, Russell, accompanied by Dora, visited Peking (as Beijing was then known outside of China) to lecture on philosophy for a year. He went with optimism and hope, seeing China as then being on a new path. Other scholars present in China at the time included John Dewey and Rabindranath Tagore, the Indian Nobel-laureate poet. Before leaving China, Russell became gravely ill with pneumonia, and incorrect reports of his death were published in the Japanese press. When the couple visited Japan on their return journey, Dora took on the role of spurning the local press by handing out notices reading "Mr. Bertrand Russell, having died according to the Japanese press, is unable to give interviews to Japanese journalists". Apparently they found this harsh and reacted resentfully. Russell supported his family during this time by writing popular books explaining matters of physics, ethics, and education to the layman.

From 1922 to 1927 the Russells divided their time between London and Cornwall, spending summers in Porthcurno. In the 1922 and 1923 general elections Russell stood as a Labour Party candidate in the Chelsea constituency, but only on the basis that he knew he was unlikely to be elected in such a safe Conservative seat, and he was unsuccessful on both occasions.

After the birth of his two children, he became interested in education, especially early childhood education. He was not satisfied with the old traditional education and thought that progressive education also had some flaws; as a result, together with Dora, Russell founded the experimental Beacon Hill School in 1927. The school was run from a succession of different locations, including its original premises at the Russells' residence, Telegraph House, near Harting, West Sussex. During this time, he published On Education, Especially in Early Childhood. On 8 July 1930, Dora gave birth to her third child Harriet Ruth. After he left the school in 1932, Dora continued it until 1943.

In 1927 Russell met Barry Fox (later Barry Stevens), who became a known Gestalt therapist and writer in later years. They developed an intense relationship, and in Fox's words: "... for three years we were very close." Fox sent her daughter Judith to Beacon Hill School. From 1927 to 1932 Russell wrote 34 letters to Fox. Upon the death of his elder brother Frank, in 1931, Russell became the 3rd Earl Russell.

Russell's marriage to Dora grew tenuous, and it reached a breaking point over her having two children with an American journalist, Griffin Barry. They separated in 1932 and finally divorced. On 18 January 1936, Russell married his third wife, an Oxford undergraduate named Patricia ("Peter") Spence, who had been his children's governess since 1930. Russell and Peter had one son, Conrad Sebastian Robert Russell, 5th Earl Russell, who became a historian and one of the leading figures in the Liberal Democrat party.

Russell returned in 1937 to the London School of Economics to lecture on the science of power. During the 1930s, Russell became a friend and collaborator of V. K. Krishna Menon, then President of the India League, the foremost lobby in the United Kingdom for Indian independence. Russell chaired the India League from 1932 to 1939.