Complex sentence: All schools of thought came under a single banner on important occasions to offer prayers which led to the formation of Ummat e Islami, which came out with the slogan "Aapka Maslak Aapko Mubarak".
Split into simpler sentences: All schools of thought came under a single banner on important occasions to offer prayers. This led to the formation of Ummat e Islami, whose slogan became "Aapka Maslak Aapko Mubarak".