by the merchants of Tiel in Gelderland (present-day Netherlands), in 1020 is believed to be the first example of a Medieval guild. The first instance of usage of the term, "guild", was the gilda mercatoria used to describe a body of merchants operating out of St. Omer, France in the 11th century and London's Hanse was formed in the 12th century. The merchants of Cologne had their house in London as early as 1157 and the Guilda Teutonicorum (German merchants warehouse) was located at Cosin Lane and Thames Street in London on the 12th century. These guilds controlled the way that trade was conducted in their region and codified rules governing the conditions of trade. Once established, merchant guild rules were often incorporated into the charters granted to market towns. By the 13th and 14th centuries, merchant guilds had acquired sufficient resources to erect guild halls in many major market towns. Medieval guild halls were used to store goods and as places for celebratory events. When not required for guild members' events, the hall often became place where townspeople could hold entertainments such as Passion plays. Guild members often cleaned streets, removed rubbish, maintained a nightwatch and provided food relief to the poor. Some medieval guilds allowed market trading to occur on the ground floor of the guildhall. In the City of London, the guilds are called "livery companies", and their guild halls are called livery halls. Guildhalls in the Low Countries The Low Countries used to have guildhalls in every city, often one gildenhuis (Dutch, literally "guild house") for each trade. They were often elaborate, ornate buildings, demonstrating the guild's status. Occasionally a single hall would be used by all the city's guilds. The guildhall was used as the offices of the deken (deacon) and other guild officers, and for meetings by the overlieden (board of directors). The guild members would occasionally be called to the guildhall for meetings on important matters. In Amsterdam, every guildhall had its gildeknecht (guild servant), often the guild's youngest member, and was guarded by a gildehond (guild dog). Every evening, the guild brothers gathered in the tavern room of the guildhall to discuss the events of the day while the gildeknecht served beer. Once a year, the guildmen would gather in the guildhall for a communal meal. The guildhall of the merchants' guild also served as de facto commodity market. Therefore, there was