Bergen-Belsen was located right next to the largest military training ground of the German Reich in Belsen. Initially it had a very specific function: it was a POW transit camp for only Jewish prisoners, to be held as exchange for German prisoners in the Western countries (they were excluded from deportation to the extermination camps).
For this reason (the hope of freedom through exchange), at first the prisoners were not directly physically maltreated by the SS and lived by different rules (so that no reports of actual maltreatments could be made in the event of an exchange), and there were also little escape attempts. In reality, little actual exchanges were ever made, though, and living circumstances deteriorated very quickly to the same level as other concentration camps. The prisoners were caught between the hope of freedom and ever-worsening living conditions.
When the camp was incorporated into the concentration camp system, this significantly altered things. Different sections of the camp were established, each fulfilling different roles, and they were strictly separated from each other. The largest group of prisoners were in the Sternlager (the original actual 'exchange' Jews forced to wear a Jewish star), but there was, amongst others, also a Frauenlager, a Neutralenlager, a Sonderlager, and an Ungarnlager (in this female camp Anne Frank and her sister Margot died). Three work detachments (sub camps) were established and prisoners were forced to work in the armaments industry: Hambühren, Unterlüss and Bomlitz.
When the Western front started advancing, the concentration camps which were close to the front had to be evacuated. Because of Bergen-Belsen's geographical location, it became one of the most important destinations for these evacuations. This led to a drastic expansion and a catastrophic overcrowding in the camp, turning Bergen-Belsen from a POW exchange camp into a de facto death camp, further worsened as the SS systematically took no serious steps to deal with the hunger and illness. When the camp was liberated, thousands of unburied corpses were found, and typhus, dysentery and tuberculosis raged. Due to those appalling living conditions, about 13,000 people still died after the liberation.
Bergen-Belsen is part of a series of journeys that I'm undertaking to photograph the blue skies precisely above the (last known) location of every single one of the 1,075 concentration camps that have ever existed, as part of an photography/book/installation project called The Blue Skies Project. The project has proven quite immense and almost impossible to hold on to single-handedly – with staggering logistics to match – but I'm hanging in there.