Hz. Abubakr (rath): died normally. Or there is a rivayah that the reason why he died when he died was the poison that a group of people gave him a year earlier. The poison was a special poison that affects after a year.
Hz. Umar (rath): was killed by a Persian Majusi when he was in prostration (prayer).
Hz. Uthmaan (rath): was killed at his home while he was reading the holy Qur'an and was fast. The suicide was ordered by a Jew called Abdullah bin Saba'. He was a Jew, but shew himself as Muslim and made too many fitnas.
Hz. Ali (rath): also was killed while he was going to the mosque for prayer. This suicide was also ordered by Abdullah bin Saba'.
I want those who see mistakes in my answer to correct them.
Thank you.
Allah is the Protector.
The Umayyad Caliphate came after the four Rightly-Guided Caliphs.
First 4 Caliphs were not missionaries to Africa , but many other companions of prophet were .
they ruled differently
they were the damascus
to northwest europe
they ruled differently
The first Four Caliphs are Called the Rightful (Rashidoon) Caliphs. They were in order of seniority: Hazrat Abubakr who died his natural death. Hazrat Umar was assasinated in the Majid i - Nabwi when he came to lead the Fajr prayer. Hazrat Usman was assasinated by the rebels. Hazrat Ali was also assinated while he came to lead the Fajr prayer. In fact, the first four Caliphs didn't keep any body guard.
All the first Four Caliphs were chosen in different ways. Later on it became a kind of Kingship, son following the father.
Sunni
Iraq
The first four Caliphs in Islam are regarded as the Khulfa-e-Rashidun or The Four Rightly Guided Caliphs. These caliphs are regarded as the most famous and comprise of Hazrat Abu Bakr, Hazrat Umar, Hazrat Usman as well as Hazrat Ali.
they finished by different political events.