Just a little speculation on the possible origins of the Y-haplogroups present among the Spanish and Portuguese... My suggestions within each haplogroup are in a decreasing order of likeliness (in my view).
R1b (69% Sp, 56% Pt) - Alpine Celts/Lusitanians/Proto-Celtic Indo European speakers (R-S28 subclade); Roman settlers (also S28); Crusader settlers from England/Low Countries/Germany (S21 subclade) ?;
E1b1b (14% Pt, 7% Sp) - Neolithic settlers from North Africa; Moorish-berber Al-Andalus settlers; Greeks, or Carthaginian/Phoenicians, along the Mediterranean coast of Spain; Romans (Central Italy: 10% E1b1b);
J2 (Pt 9.5%, Sp 8%) - Near the Mediterranean coast: Greeks/Carthaginians/Romans; in the rest of the peninsula, Romans (central Italy: 19.5% J2);
I2a/I2b (Sp 5.5%, Pt 4.5%) - Paleolithic Cro-Magnons from Central/Southern Europe, native Iberians;
G2a (Pt 6.5%, Sp 3%) - Neolithic farmers/shepherds from beyond the Pyrenees; Romans (Central Italy: 8.5% G2a); Alans (G2a1 subclade);
T (Pt 2.5%, Sp 2.5%) - Neolithic Middle Eastern farmers;
J1 (Pt 3%, Sp 1.5%) - Arabic Al-Andalus settlers; older Jewish settlers; neolithic Middle Eastern settlers;
I1 (Pt 2%, Sp 1.5%) - Visigoths, Suevi, Vandals;
R1a (Sp 2%, Pt 1.5%) - Visigoths, Suevi, Vandals; Slavic slaves (saqaliba) in Al-Andalus ?