This page concerns Lydian Bageis, Bagis or Bage, not to be confounded with Bagae in Numidia.
Bageis ( Ancient Greek: Βάγεις), Bagis (Βάγις), or Bage (Βάγη) was a city in the Roman province of Lydia in Asia Minor (modern Turkey).
The name of the city appears in the form
Bageis (in the genitive plural case of the name of its inhabitants, ΒΑΓΝΩΝ or ΒΑΓΗΝΩΝ) on its coins, but Bagis is the form given in the of Synecdemos Hierocles, and Bage in later . Notitiae Episcopatuum  Some of its coins add the additional name of KAISAREΩN apparently denoting the additional city name of Caesarea. 
Inscriptions uncovered by Keppel place the ancient town near
Sirghe on the left (south) side of the Hermos River.  Modern scholars pinpoint a site at  Güre. 
see of Bagis, being in the Roman province of Lydia was a suffragan of Sardis, the capital of the province.
The acts of the
First Council of Nicaea (325) mention a Pollio as bishop of Baris in that province. Since there is no evidence of a bishopric of that name, Janin (1931), following  Adolf von Harnack, consider "Baris" to be an error for "Bagis", while Pétrirdès (1907), who cites  Heinrich Gelzer and C. H. Turner, does not accept that correction. Other known bishops of Bagis are Chrysapius or Chrysanthus, who was at the  Robber Council of Ephesus in 449, Leonides, who was a signatory of the joint letter that the bishops of Lydia sent in 459 to Byzantine Emperor Leo I the Thracian with regard to the murder of Proterius of Alexandria, and Basilius and Clemens, who were at the Council of Constantinople (879), presumably one of them ordained by  Patriarch Ignatius of Constantinople, the other by Photius. 
Bagis must have disappeared as a residential see during the
Turkish- Byzantine wars, perhaps in the 12th century, although it continued to be listed in . Notitiae Episcopatuum
No longer a residential bishopric, Bagis is today listed by the
Catholic Church as a titular see. a list of  titular bishops includes:
St. Francesco Antonio Domenico Fogolla, (28 Jun 1898 Appointed - 9 Jul 1900)
Joaquim Silvério de Souza † (16 Nov 1901 Appointed - 17 May 1905)Bishop of Diamantina.
Celestin Ibáñez y Aparicio,(12 Apr 1911 - 11 Apr 1946) Bishop of Yan’an [Yenan])
Jorge Marcos de Oliveira (3 Aug 1946 Appointed - 26 Jul 1954, Bishop of Santo André,
Sao Paulo Ramón Pastor Bogarín Argaña (1 Dec 1954 Appointed - 19 Jan 1957, Bishop of San Juan Bautista de las Misiones
Albert Sanschagrin, (12 Aug 1957 - 13 Jun 1967) Bishop of Saint-Hyacinthe,
Québec) José Afonso Ribeiro, (29 Jan 1979 Appointed - 6 Jul 1988, Prelate of Borba, Amazonas)
João Evangelista Martins Terra (17 Aug 1988 Appointed - )
^ a b c d e Raymond Janin, v.
Bagé, in , vol. VI, 1932, col. 201 Dictionnaire d'Histoire et de Géographie ecclésiastiques
^ a b c d
Sophrone Pétridès, "Bageis" in Catholic Encyclopedia (New York 1907)
Wildwinds.com - Ancient coins from Bageis
Richard Talbert, ed. (2000). . Princeton University Press. p. 62, and directory notes accompanying. Barrington Atlas of the Greek and Roman World
Lund University. . Digital Atlas of the Roman Empire
Mission und Ausbreitung des Christentums in den ersten drei Jahrhunderten, p. 486
Annuario Pontificio 2013 (Libreria Editrice Vaticana 2013 ISBN 978-88-209-9070-1), p. 845 This article incorporates text from a publication now in the public domain: Smith, William, ed. (1854–1857). "Bage". . London: John Murray. Dictionary of Greek and Roman Geography
Large database of ancient coins of Bagis on wildwinds.com