On his daily walks around Budapest, the Irish photographer Nigel Swann, who has lived in the city for over 10 years, has photographed the entrances to hundreds of apartment blocks – their doors, letterboxes, graffiti, vitrines and facades in various states of disrepair.

District VII, Dohany, utca 59, Budapest

Many of the blocks were built during the patriotic construction boom of the 1880s and 90s, while others are early art deco masterpieces, and later buildings are the pioneering work of Bauhaus disciples.

Nigel’s pictures present us with doorways – domestic openings in a hectic cityscape inscribed with lingering evidence of human habitation. But actual lives are noticeable only in their absence. There are no people.

District VII, Akácfa utca

Unbeknown to him, many of them 70 years ago were “yellow-star houses”. Upon discovering a list of said houses, he revisited and rephotographed all of them.

From 21 June until late November 1944, all Jewish Budapest citizens were obliged to wear the yellow star and live under curfew in a designated house with the same marking, usually made out of cardboard. Throughout the city there were almost 2,000 such residences, accommodating around 220,000 people for almost six months, until two large ghettoes were established near the end of the war. The aim of this forced mass relocation was to prepare them for deportation, so each family was allowed just one room.

Paulay Ede, utca 43

The yellow-star houses were unique to Budapest: nowhere else in Nazi-occupied Europe were houses reserved for Jews and forced to have yellow stars. This was, after all, an interim measure for them – a way station en route to the death camps.

Although around 1,600 former yellow-star houses are still used as homes today, their former identities were largely unknown until 2014. Barely a handful of archive photographs of them remain: all Hungarian Jews had their cameras (plus their radios and bicycles) confiscated in April 1944 – another blow in a long series of humiliating acts of legislation. After the war, the yellow-star houses were a subject that remained off-limits in many families. Neither victims nor perpetrators wanted to talk.

Vörösmarty, utca 20

Of the visible clues that remain, how can we fathom acts of unspeakable, organised violence carried out against a large section of the community in a modern metropolis? Nigel’s photographs are one answer. They allow us to imagine the human lives and deaths that these yellow-star house doors conceal.