Where does “Sandqvist” come from?

Sandqvist (Swedish) comes from Swedish sänd, from Old Swedish sander, from Old Norse sannr, from Proto-Germanic sanþaz, from Proto-Indo-European h₁sónts, from Proto-Indo-European h₁ēs- — to be.

Ancestry of “Sandqvist”, step by step

Sandqvist traces back through two separate lines of ancestry.

via Swedish sänd

Step	Language	Word	Meaning
1	Swedish	sänd	sand (finely ground rock)
2	Old Swedish	sander	true, real
3	Old Norse	sannr	true
4	Proto-Germanic	sanþaz	true, real
5	Proto-Indo-European	h₁sónts	active participle of *h₁ésti; being, existence;...
6	Proto-Indo-European	h₁ēs-	to be

via Swedish kvist

Step	Language	Word	Meaning
1	Swedish	kvist	a twig; a stick; a dormer
2	Old Norse	kvistr	twig, branch
3	Proto-Germanic	kwastuz	tuft; tassel
4	Proto-Indo-European	gʷes-	twig; leafwork

Every word from Proto-Indo-European h₁ēs- →Every word from Proto-Indo-European h₁sónts →Every word from Proto-Germanic sanþaz →