http://www.biblewalks.com/Sites/DavidTomb.html King David was buried at about 1000 BCE, probably in the area south of the present walled city, where the "city of David" was located. This is what the Bible tells us (1 Kings 2: 9): "So David slept with his fathers, and was buried in the city of David". Other Kings from the house of David were buried there too, as implied in Nehemiah 3, 16: "...the sepulchres of David...".
After several centuries the tombs were probably destroyed and buried under the newly expanding city. This may have happened during the 1st or 2nd C CE.
##Roman period - Mount Zion
Mount Zion was not part of the city of David, and is located several hundred meters away to the north-west. The hill was incorporated into the new city only in the Hellenistic and early Roman periods - within the new walls of the "upper" city.
An archaeological survey was conducted in 1948 after the building suffered from damages during the Independence war. According to the survey, the Roman level (end of 1st C CE) was the "ground" level of the present structure. On top of it there were several layers of construction. Based on the findings, the original building may have been an early synagogue, which was built after the destruction of the temple.
##Byzantine period
Several hundred years later, during the Byzantine period, the early Christians built several churches around Mount Zion. The archaeological survey identified the second level in this site, above the early Roman level, was a Byzantine building.
##Persian and Arab conquest
After the Arab conquest, the area remained in ruins from the 7th C until the 12th C.
The tradition of the location of King David's tomb on Mount Zion was first documented at this time (9th C).
##Crusaders
The Crusaders rebuilt some of the structures on Mount Zion, as well as many sections of Jerusalem. The archaeologists found a level from that period (12-13th C), above the Byzantine level and below the present floor.
After the Crusaders retreated the structured was cared by Monks for some time.
##Ottomans
The Ottomans did not include the area inside the 16th C wall, but regarded the site as a Holy place - the site of the King David's tomb. They banished the monks, and transformed it into a mosque, E-Nebi Daud, or: the prophet David. In the building around the site lived a Muslim family, who held the keys to the site.
In 1864 an archaeological excavation revealed a shallow cave (35M x 15M x 4M) under the ground level.
##Modern times
The Jews and Christians were banned for hundreds of years to freely visit the site. This changed in 1948 when the Independent Israel received control over the Holy site, and after the city was reunited in 1967 the site became one of the major Religious sites in the Holy Land, cherished by the three religions.