History of Agnihotra
The Agnihotra that we know now, can be traced back to 1942. It was resurrected by Shree Gajanan Maharaj of Shivpuri, a disciple of Gangadhar Maharaj. Those days Shivpuri was called as Akkalkot. Shree Gangadhar Maharaj was disciple of Balatpa, who in turn was the disciple of Shree Swami Samartha, the third incarnation of Lord Dattatreya.
Now Shri Gajanan Maharaj had a sighting of Lord Parshuram. Lord Parshuram appeared in flesh and body and he asked Gajanan Maharaj to spread agnihotra all over the world, Because it was the need of the time. Hence Gajanan Maharaj promoted it in the form that we see today. This concise form is to be done exactly at the time of sunrise and sunset everyday. This whole ceremony lasts for about 5 to 10 min.
Then in 1969 Shri Gajanan Maharaj, initiated Shri Vasant Rao Paranjpe, the father of agnihotra that we know of today, in this path. Then on his orders, In 1972 Shri Vasanth Rao Paranjpe went to Peru to spread agnihotra.
In 1984 Shri Vasanth Rao Paranjpe took the initiative of spreading it all over the world.
The agnihotra that we know today, is not the one that was conceived during the vedic times. Agnihotra was that fire which was burnt at the time of marriage. The person was supposed to carry the fire home and thereafter keep it burning till the end of his life. This fire was kept burning all the time without letting it get extinguished. And every other fire that was used in the house like cooking, heating and other domestic application was basically coming from that original agnihotra fire. And the people who were following this kind of rituals were called as agnihotris.