In his autobiography, Jawahar Lal Nehru, India's first prime minister states that his ancestors who came from Kashmir and were kashmiri pandits adopted the surname Nehru as they used to live next to a "nehar" (hindi word for canal). The name initially became Kaul-Nehru but the Kaul was dropped later.
During the turmoil in early nineteenth century, two known branches of this family moved in different directions - one to Allahbad and the other to Ambala. Both these branches have produced great politicians, freedom fighters, bureaucrats, judges and authors.
Geni probably has 80% or more names of all people who ever carried the surname Nehru