元服に際して、外祖父（母方の父）にあたる、鎌倉幕府第3代執権の北条泰時から偏諱を賜わり、泰氏と名乗った。嘉禎2年（1236年）丹後守、嘉禎3年（1237年）に宮内少輔になり、鎌倉幕府4代将軍藤原頼経に近仕した。宝治合戦の直前、宝治元年（1247年）3月2日に、時頼の姉妹である泰氏の正室が死去。宮騒動、宝治合戦に続く執権・北条時頼による得宗専制体制強化の過程で、有力御家人の勢力が削がれていく中でも、父の義氏は幕府宿老として重んじられていたが、建長3年（1251年）12月、泰氏は36歳で無断出家してしまい、幕府の許可無く出家したことを咎められ、自身が拝領した下総埴生荘を没収されて足利の本領に閉居した。以降、政治の舞台に出ることはなくなったとされる。泰氏の出家の翌年3月には5代将軍藤原頼嗣が京へ強制送還されていることから、何らかの関連性があったと考えられているが、無断出家をした原因は不明である。なお義氏は、泰氏出家後も地位や所領を保ち、頼氏には義氏の所領が相続されている。家内にあっては、はじめ名越流北条氏の北条朝時の娘を正室に迎え、斯波家氏、渋川義顕を儲けるが、後に得宗家の北条時氏の娘と婚姻することになり、これを正室として足利頼氏を儲けた。得宗家との婚姻により、朝時の娘は側室に移され、後継者と目されていた家氏は廃嫡、尾張足利家として後の斯波氏の祖となり、足利宗家嫡男も正室の子である頼氏となった。このような経緯もあり、足利一門の中でも斯波氏と渋川氏格別の家格を誇ることとなる。六男の基氏は下野の足利荘のうち加古郷を分領され加古氏の祖となった。さらに後には桜井判官代俊光の娘との間に、一色公深を儲ける。公深は桜井判官代俊光より三河国幡豆郡吉良荘の地頭の身分を譲り受け、吉良荘一色郷（愛知県西尾市一色町）に住み、足利家の四職のひとつの家となる一色氏の祖となる。文永2年（1265年）に智光寺を建立した。室町幕府を開府する前の足利氏の勢力は、父・義氏と泰氏の頃が最大だった。その頃を偲ばせる、泰氏が足利氏の氏寺・鑁阿寺南大門に足利一党の武者500騎を勢揃いさせた故事に因んだ節分鎧年越という行事が今も足利市で行われている。
明治製菓「明治チョコレート」のCMソングに使用された。1981年1月22日に『ザ・ベストテン』の「今週のスポットライト」コーナーに取り上げられると、翌週からリクエストはがきが急増。当番組には同年2月12日に第7位で初の10位以内入りを果たす。その後2月19日・2月26日・3月12日と最高第5位（通算3週）まで上昇、4月2日（第7位）迄合計8週間連続でランクイン。さらにレコード売上は45万枚を記録、五十嵐としては最大のヒットソングとなり、1981年冬季の代表曲となった。
In Ukraine the anarcho-communist guerrilla leader Nestor Makhno led an independent anarchist army in Ukraine during the Russian Civil War. A commander of the peasant Revolutionary Insurrectionary Army of Ukraine, also known as the Anarchist Black Army, Makhno led a guerrilla campaign during the Russian Civil War.  The revolutionary autonomous movement of which he was a part made various tactical military pacts while fighting various forces of reaction and organizing the Free Territory of Ukraine, an anarchist society, committed to resisting state authority, whether capitalist or Bolshevik. After successfully repelling Austro-Hungarian, White, and Ukrainian Nationalist forces, the Makhnovists militia forces and anarchist communist territories in the Ukraine were eventually crushed by Bolshevik military forces.In Mexico Ricardo Flores Magón was one of the major thinkers of the Mexican Revolution and the Mexican revolutionary movement in the Partido Liberal Mexicano. Kropotkin's The Conquest of Bread, which Flores Magón considered a kind of anarchist bible, served as basis for the short-lived revolutionary communes in Baja California during the "Magónista" Revolt of 1911.A group of exiled Russian anarchists attempted to address and explain the anarchist movement's failures during the Russian Revolution. They wrote the Organizational Platform of the General Union of Anarchists which was written in 1926 by Dielo Truda ("Workers' Cause"). The pamphlet is an analysis of the basic anarchist beliefs, a vision of an anarchist society, and recommendations as to how an anarchist organization should be structured. The four main principles by which an anarchist organization should operate, according to the Platform, are ideological unity, tactical unity, collective action, and federalism. The platform argues that "We have vital need of an organization which, having attracted most of the participants in the anarchist movement, would establish a common tactical and political line for anarchism and thereby serve as a guide for the whole movement".The Platform attracted strong criticism from many sectors on the anarchist movement of the time including some of the most influential anarchists such as Voline, Errico Malatesta, Luigi Fabbri, Camillo Berneri, Max Nettlau, Alexander Berkman, Emma Goldman and Gregori Maximoff.  Malatesta, after initially opposing the Platform, later came to agreement with the Platform confirming that the original difference of opinion was due to linguistic confusion: "...I find myself more or less in agreement with their way of conceiving the anarchist organisation (being very far from the authoritarian spirit which the "Platform" seemed to reveal) and I confirm my belief that behind the linguistic differences really lie identical positions." Two texts were made by the anarchist communists Sebastian Faure and Volin as responses to the Platform, each proposing different models, are the basis for what became known as the organisation of synthesis, or simply "synthesism".Voline published in 1924 a paper calling for "the anarchist synthesis" and was also the author of the article in Sebastian Faure's Encyclopedie Anarchiste on the same topic. The main purpose behind the synthesis was that the anarchist movement in most countries was divided into three main tendencies: communist anarchism, anarcho-syndicalism, and individualist anarchism and so such an organization could contain anarchists of this 3 tendencies very well. Faure in his text "Anarchist synthesis" has the view that "these currents were not contradictory but complementary, each having a role within anarchism: anarcho-syndicalism as the strength of the mass organisations and the best way for the practice of anarchism; libertarian communism as a proposed future society based on the distribution of the fruits of labour according to the needs of each one; anarcho-individualism as a negation of oppression and affirming the individual right to development of the individual, seeking to please them in every way.