"evergreen tree," 1660s, from spruse
(adj.) "made of spruce wood" (early 15c.), lit. "from Prussia," from Spruce, Sprws
(late 14c.), unexplained alterations of Pruce
"Prussia," from O.Fr. Spruce
seems to have been a generic term for commodities brought to England by Hanseatic merchants (beer, board, leather, see spruce
(v.)), and the tree was believed to have come from Prussia.