So in all the communist revolutions I've heard about, most of them seem to end in the execution of thousands of people, landlords, enemies of the party and so fourth.
I know this happened in Russia, China, Guatemala, and Vietnam (to a smaller extent i think, according to Ken Burns amazing documentary about it).
Obviously if there was a civil war many people would die, but i'm talking about after the Communist party had already taken over.
Are there instances of a peaceful transfer of power to a communist government? If there isn't, why not?
Thank you!
EDIT: Sorry i meant the Khmer Rouge regime of Cambodia, not Guatemala!
In terms of Marxist ideology, there is an expectation that capitalism can only be overthrown by a violent seizure of power (whether it's directly by the proletariat, as Marx tended to think, or by a vanguard party on the proletariat's behalf, as Lenin theorized). Of course plenty of followers of Marxist thought decided that change could occur through participation in electoral politics - that's where we get figures like Wilhelm Liebknicht, August Bebel, and the German Social Demoratic Party (and the rise of socialist parties elsewhere). But to stick with the question I'll focus on Leninists (and Stalinists, Trotskyists and Maoists) since that's what tends to be grouped under communism.
Probably the best examples of peaceful assumption of power and rule by communist parties are: the state of Kerala in India has had governments under the Communist Party of India (and one of it's successors, the Communist Party of India (Marxist)) off and on since 1957. The current Chief Minister of Kerala, Pinarayi Vijayan, is a member of the CPI(M) Politburo. The Communist governments in Kerala have historically pushed for land reform and for greater education (Kerala has one of the highest literacy rates in India), but without any mass violence or repression. The CPI(M) also controlled the state government of West Bengal from 1977 until 2011 through consistently winning elections in that period.
The South African Communist Party has long had a friendly relationship with the African National Congress and Congress of South African Trade Unions in the so-called "Triple Alliance". The SACP doesn't contest elections, but it historically has had members elected to the National Executive Committee of the ANC and has influenced policy mostly through that means.
In terms of Guatemala, if you're referring to Arbenz's presidency, I would note that it was neither violent nor technically communist. Arbenz was personally friendly with Guatemalan communists and relaxed restrictions on the party, and implemented a wide-ranging land reform, but he was not a Communist himself, gained power through a democratic election, and implemented the reforms without mass repression. His overthrow in a coup that was supported by the US government was violent, however.