The Vallahades (Βαλαχάδες) or Valaades (Βαλαάδες) were a Muslim Macedonian Greek population who lived along the river Haliacmon in southwest Greek Macedonia, in and around Anaselitsa (modern Neapoli) and Grevena. They numbered about 17,000 in the early 20th century. They are a frequently referred-to community of late-Ottoman Empire converts to Islam, because, like the Cretan Muslims, and unlike most other communities of Greek Muslims, the Vallahades retained many aspects of their Greek culture and continued to speak Greek for both private and public purposes. Most other Greek converts to Islam from Macedonia, Thrace, and Epirus generally adopted the Ottoman Turkish language and culture and thereby assimilated into mainstream Ottoman society. The name Vallahades comes from the Ottoman Turkish Islamic expression والله 'by God'. They were also known as Φούτσιδες, Foútsides; from φούτσι μ', foútsi m, which is a corruption of the Greek αδελφούτσι μου, adelfoútsi mou 'my brother'. They were pejoratively called Μεσημέρηδες, Mesimérides, because their imams, uneducated and not knowing much Turkish, announced noon prayer by shouting in Greek Μεσημέρι, Mesiméri 'noon'. Though some Western travelers speculated that Vallahades is connected to the ethnonym Vlach, this is improbable, as the Vallahades were always Greek-speaking with no detectable Vlach influences. In Turkish they are known as Patriyotlar 'patriots'; sometimes Rumyöz 'Greek' is used. The Vallahades were descendants of Greek-speaking Eastern Orthodox Christians from southwestern Greek Macedonia who probably converted to Islam gradually and in several stages between the 16th and 19th centuries. The Vallahades themselves attributed their conversion to the activities of two Greek Janissary sergeants (Ottoman Turkish: çavuş) in the late 17th century who were originally recruited from the same part of southwestern Macedonia and then sent back to the area by the sultan to proselytize among the Greek Christians living there.