In that indicator, pre-Islamic Iberians are people who lived in Spain before it was conquered by Islam around the 8th century AD. In other words, it can be said to be of native Spanish descent. As Spain became Islamic, many people converted.
Berbers are indigenous people of North Africa
Middleston people came from the Middle East
After Christian forces recaptured the Iberian Peninsula in the 15th century, they expelled large numbers of Berbers and Arabs, but they also expelled people who were indigenous to Spain but adhered to the Islamic faith, and it is said that many of them went to Tunisia, Morocco, and Algeria.
So, even today, 20% of Moroccans, 10-15% of Algerians, and 10% of Tunisians are said to be descendants of indigenous Spaniards who were expelled for believing in Islam.