History:

The Kundra surnames spread was a mix of people choosing to move and being forced to move. People might have moved to find better jobs or marry into families in new places, slowly spreading the name. Imagine traders traveling far or families moving for better farming. Sadly, wars, hunger, or political problems also forced people to move, taking this surname with them to new homes. Where this surname ended up depended on these events, with some places having more people with this surname because more people with this surname moved there. Over time, these movements created the pattern we see today.

Description:

Its spread likely reflects movement and historical happenings, making a single explanation impossible.

But thinking about how names usually change, we might see things like "Kundraa" (with an extra "a"), or "Cundra" (a slight letter change). Adding things to the end, like "-son," is also possible, but wed need more info to know for sure.