Why do the Shi'as curse the first three Caliphs?

Answer 1

The practice of this originates back to the Safavid Dynasty in Iran. The conqueror Isma'il I, who proclaimed Shi'ism as the state religion, was very anti-Sunni. Iran, a Sunni majority at the time, was forced to convert to Shi'ism by Ismail I. To do this, one thing he imposed was the practice of cursing the first three Khalifas, Abu Bakr, Othman, and Omar, as a way of strengthening Shi'ism in his empire. The Safavid Dynasty became the origin of modern Shi'ism, and the cause of its spread "by the sword," or by violence. Thus, many Shi'as today still partake in these practices, regardless of the fact the Khalifas were highly trusted companions of the Prophet Muhammad (S).

Answer 2

Historically, some of the Muslims after Prophet Muhammad death were supporting that who follows the prophet should be of the prophet family. Accordingly, they were supporting that the Caliph after Prophet death should be Ali Ibn Abou Taleb (The prophet cousin and the husband of his daughter Fatima God be pleased with her and him). Those Muslims are called afterwards the Shiites. However, Ali (God pleased with him supported the elected first Caliph after the prophet (Abou Bakr), the elected second Caliph (Omar) and the elected third Caliph (Othman). He (Ali Ibn Abou Taleb) was the fourth elected Caliph. The rejection of those Muslims was only during the election process but never translated, after the election, into violence or protest or any kind of dissatisfaction.

Answer 3

The Umayyads directly opposed Ali and his sons Hassan and Hussein, who Shiites believed were the rightful inheritors of the Caliphate. The Shiites, accordingly, rejected the Umayyads' supposed mandate from the Sunni community.