Rajab is Seventh month of Islamic year, In islamic history Islamic month of Rajab preserve so many historic movements and events some are as below : 

Hijri Date Events
1 Rajab Wiladat of 5th Imam Muhammad Baqir (A.S.)
3 Rajab Shahadat of 10th Imam Ali Un-Naqi (A.S.)
10 Rajab Wiladat of 9th Imam Muhammad At-Taqi (A.S.)
13 Rajab Wiladat of the first Imam, Imam Ali (A.S.)
15 Rajab Wafat of Bibi Zainab (A.S.)
25 Rajab Shahadat of 7th Imam Musa e-Kazim (A.S.)
26 Rajab Wafat of Abu Talib (A.S.)
27 Rajab Me'raj
27 Rajab The Beginning of the Prophetic Mission