The Uppsala Conflict Data Program (UCDP) is a university-based data collection program on organised violence. The program continuously gathers information on armed conflict and other types of organised violence, which is subsequently published in the annual booklet “States in Armed Conflict” and also available from the program’s database. The program collects both quantitative and qualitative data on organised violence; data which is used both by researchers in the social sciences and by journalists and policymakers

The UCDP came about during the mid-1980s when it became clear that more systematic and global data on armed conflicts was necessary for the ever-growing academic discipline of peace and conflict research. Initially the program collected data only on so-called “armed conflict”, defined as fighting exceeding 25 battle-related deaths between two actors of which at least one is a state. In later years the data gathering has grown, and the program now also collects data on “non-state conflict” (where no party is the state) and “one-sided violence” (where an organised group attacks unarmed civilians). From a meagre beginning the UCDP’s data is now annually published in such renowned publications as the SIPRI Yearbook and the Journal of Peace Research. In the early 2000s the program also created an online database, where data is available for any user, free of charge.

Uppsala (Swedish pronunciation: [ˈɵpːˈsɑːla]; older spelling Upsala) is the capital of Uppsala County and the fourth largest city of Sweden. It had 140,454 inhabitants in 2010.

Located 67 km north of the capital, Stockholm, it is also the seat of the Uppsala Municipality. Since 1164, Uppsala has been the ecclesiastical centre of Sweden, being the seat of the Archbishop of the Church of Sweden. Founded in 1477, Uppsala University is the oldest centre of higher education in Scandinavia.

Uppsala was originally located a few kilometres to the north, at a location now known as Gamla Uppsala (Old Uppsala). Today's Uppsala was then called Östra Aros. (Old) Uppsala was, according to medieval writer Adam of Bremen, the main pagan centre of Sweden, and the Temple at Uppsala contained magnificent idols of the Æsir gods.

As a replacement for the Scandinavian gods, Uppsala was made into a strong Christian centre. A bishop was soon consecrated, and in 1164 Uppsala was made into an archdiocese, with Stefan, a monk from Alvastra Abbey, being consecrated the first Archbishop of Uppsala and primate of Sweden.