Usually, all you see from the era are some colourful posters that would suggest that everything was fine and dandy with the two countries, with the Soviet Union as the big brother pointing towards a communist utopia. I know that Mao couldn't stand Khrushchev, which is why their relations started deteriorating in the mid-fifties. But what were they like before? What were they like in practice, when they actually had to implement reforms together? What further reading could I do on the topic? Until now, I've found Jersild's Sino-Soviet Alliance and Lüthi's Sino-Soviet Split. Should I start with those?
Thanks.
Sino-Soviet relations can be traced back to the coming to power of Lenin, when the new regime renounced Russia's rights under the Unequal Treaties to the exploitation of China. Throughout the Warlord Era, the USSR and Comintern under the direction of Lenin and Stalin delivered aid and advice to the Kuomintang, at that point the favoured body for revolution in China as part of the USSR's greater anti-Western geopolitical strategy. The CCP was not the favoured party until after the "White Terror," whereby Chiang Kai-shek purged the KMT of the CCP members who had been allowed in. The Left-wing of the KMT under Wang Jingwei initially opposed this, but after Stalin's plot for the CCP to take over the KMT from the inside was revealed, the left of the KMT succumbed to Chiang and pursued a common policy towards the CCP.
After the CCP's victory over the KMT in the Civil War and their coming to power, the PRC and the USSR were natural allies. The Sino-Soviet Treaty of Friendship, Alliance, and Mutual Assistance was signed in 1950, and the two regimes fostered the sort of trade relationship you would imagine between a developing and developed country. The PRC exported food, minerals, and raw materials to the USSR, in return for machinery and war equipment. The PRC received loans - not aid - to the tune of $1,325,000,000 from the USSR between 1950 and 1957, split roughly 2:1 in favour of military over industry. The PRC had repaid just under half of this by 1958.
China's quite successful first Five Year Plan was overseen with the help and advice of Soviet advisors. During this period, and since the relationship with the KMT, the Chinese sent officials to Moscow to learn from the USSR, and the Soviets sent advisors to aid military and industrial development in China.
After Khrushchev came to power, and due to Mao's own domestic political issues which I touched upon here in relation to the Great Leap Forward, Sino-Soviet relations altered as Khrushchev urged de-Stalinisation, which undermined Mao's own legitimacy (as he had justified his political campaigns by way of comparison to Stalin's cult of personality).
My knowledge of this tends to come from my study of Mao and the early PRC, for which I will always advise reading Kenneth Lieberthal's "Governing China: From Revolution to Reform" as a excellent starting point. For more on the relationship between China and the USSR, E. H. Carr's work touches on some of the early history in pre-Communist China. On this topic in particular, I would recommended a recent publication by Zhihua Shen and Yafeng Xia, Mao and the Sino–Soviet Partnership, 1945–1959: A New History.