Far less than 500 years. Christian Serbs were a majority after WW2. Slowly the Muslims whittled down the Christian population in Kosovo via legal/illegal immigration, via out breeding Serbs, by driving Serbs out of Kosovo
Exactly the same thing happened in Lebanon. I'm sick to the gills of Muslims hijacking Christian nations and multi ethnic nations. Your kooky Muslims have another tactic in India. A few provinces in India are heading to Muslim majority and your Muzzies want to cleave them off to make mini Pakistanis from them. Muslims will never live in peace next to non Muslim populations. Not for extended times.
Dennis, Albanians have been the majority in what is now Kosovo for a couple hundred years and their proportion of the population in Kosovo actually decreased in the first part of the 20th Century.
According to the Library of Congress country study on Albania, Albanians have been living in Kosovo for hundreds of years and have constituted the vast majority of Kosovo's population since at least the 18th Century." See the 1992 Library of Congress Albania Country Study. (go to chapter 1, The Balkan Wars section).
Some early 20th Century studies in H.R. Wilkinsons Maps & Politics book on south Balkans ethnography (ya gotta go to the library for that) put the Albanians at over 90% in what is now Kosovo. Edith Durhams very entertaining 1909 book High Albania on her travels in northern Albania gives further testimony of Albanian predominance in Kosovo.
The 1990 Library of Congress Country Study on Yugoslavia (Go to Chapter 1, Political Life in the 1920s) also states After the mid-eighteenth century, Albanians became a majority in Kosovo. Later on the same page it talks of Serb efforts to fix the ethnic balance: in 1920 Belgrade began a drive to resettle Serbs in the region. Coercion, illegal expropriation of Albanian-owned land, and forced deportations marred this campaign. When Albanians attacked Serbian settlements and government institutions, the police seized Albanian property, imprisoned families, and destroyed homes.
In 1921, 65.8% of Kosovo's population was Albanian and 26% was Serbian based on a government census that counted by mother tongue. Figures from the 1939 census (scroll about halfway down) show that the non-Slav population (ethnic Albanians, Turks, Gypsies, etc.) numbered 422,828 people, or 65,6%, the native Slav population accounted for 25,2% and the settlers (mostly Serbs) for 9,2% . Even the 1944 briefing paper given to President Roosevelt by his Envoy Myron Taylor on disputed territories in Europe describes the ethnic composition of Kosovo as two-thirds Albanians.
The post WWII censuses stayed at about 2/3 Albanians in Kosovo1948: (65%), 1953 (65%), 1961 (67%) until the 1970s when with the highest birth-rate in Europe--Kosovar Albanians jumped to 74% in 1971, 78% in 1978 and estimates of 80-90% in the 1990s.