It was offered in the home of H. Ayesha RA. in small groups 2 or 3 person at a time as room was small ..
Hazrat Muhammad PBUH
Hazrat Hassan a s offered the namaz e janaza of Hazrat Ali as
Hazrat abu huraira r.a
All Muslims in Madina .
Allama Iqbal Ki Namaz e Janaza Molvi Ghulam Murshid Ne Parhae.‎ FB.com/farooq.ksa1
حضرت عثمان کے جنازہ نماز مین کون کون شریک تھا
Hazrat Ali AS lead the Janaza Prayer of Bibi Fatima and then Buried the blessed Body the same night next another prayer was held to offer Ghaibana Namaz e janaza lead by then Caliph Hazrat Abu Bakar RA
The Arch Angel Hazrat Gabriel demonstrated before the holy Prophet Muhammad (SAW) how to offer Namaz and the timings of offering Namaz.
If a Muslim does not read Namaz then, you can not go to his/her janaza, I wouldn't go if some one die and he did not read Namaz.
Ahzam Chisti
Abdul Hamid Badayuni performed the Funeral of Allama Muhammad Iqbal.
Yes. Youmayoffer Namaz behind any Muslim. Only some sects of the Shias have different kind of namaz i janaza.