The two neighbouring buildings on Na Poříčí were originally built by Banka československých legií in 1921–39. The first to be built in 1921–23 was building number 1046, nowadays known as Legiobanka. The building was designed by the famous architect Josef Gočár in a Rondocubist style.
Gočár invited his friends and a superb artists to cooperate on Legiobanka: Jan Štursa, the author of four statues of legionaries located above the main entrance, Otto Gutfreund, who created a relief fascia on the parapet of the second floor of Return of the Legions by František Kysela, who is the author of the internal artistic decoration and stained-glass windows of the glazed trefoil arch above the banking hall.
Legiobanka did well, so in 1937–38 it had a second building added next door — a modern building in the Functionalist style designed by the architect František Marek, which is connected with Gočár’s Rondocubist building. The second building is called the Golden Spike, which relates to the decoration on the second floor with a wrought spike motif designed by Josef Kaplický.
The complex of both buildings was purchased in 1990 by ČSOB, which commenced grand renovation work which was performed in 1991–94 according to a concept by the architect Vojtěch Obadálek. The basement theatre hall was also renovated and theatre space with one of the most modern designs of the late 20th century in the Czech Republic was established there — the Archa Theatre.