Most of Spain other than the north-west (Galicia), the north-east (Catalonia) and the south (Andalucia)
Yes, it was one of the two belligerent nations.
The Moors controlled a large part of the Iberian Peninsula beginning in 711 until they were expelled in 1492 by King Fernando and Isabel. The Moors' last possession was the Alhambra in Granada.
The Pyrenees Mountains are in northern Spain.
Spain is part of the Mediterranean Vegetation Biome. Everything except the north coast along the Bay of Biscay is in this classification.