Khatris and Aroras were the trading, banking, clerical and administrative communities of Punjab. All ten Gurus were Khatris.
They ran the money trade across a very wide area: Punjabi Khatri and Arora firms had agents in Kabul, Bukhara, Astrakhan and Central Asia, and Multani bankers financed trade across the region for centuries.
They provided the clerical and administrative staff of the Mughal, Sikh and British administrations in Punjab, and the towns of west Punjab were substantially Hindu and Sikh trading populations in a Muslim-majority countryside.
In 1947 that urban population moved almost entirely to India. The commercial recovery of Ludhiana, Jalandhar, Amritsar and Delhi after 1947 was largely their work, and a very large share of Indian business families of Punjabi origin descend from that migration.
The towns they left in west Punjab lost their commercial class in a single year and the towns they came to doubled in size.
The Gurus were Khatris, all ten of them, from four subgroups. That is a fact about the community's place in the region as much as about the lineage.
Khatris and Aroras held the trade, the accounts and the revenue service across the province and out along the routes into Afghanistan and Central Asia. The Multani firm was a recognised institution at Kabul and Bukhara.
They were overwhelmingly urban and overwhelmingly in west Punjab and Sindh, and 1947 moved almost all of them east. Delhi's business class, and much of Indian Punjab's, is that migration.