You are absolutely correct. The Trocmi, Tolistobogii and Volcae Tectosages led by Leonorius and Loutorius land in Anatolia in 278BC. Imported by Nicomedes I of Bithynia fallowing their successful siege of Byzantion and the hellespont in general (many of these land gains may have been reversed by Antigonas Gonatas.) Though Leonorius and Loutorius fall from the pages of history during this time the Celts pillage Anatolia prompting Antiochus I "The Savior" to engage them in battle. Where the Galatai are defeated. Though I'm not familiar with the peace terms it's clear that they where made before 274 as Antiochus' attentions immediately shifted to Ptolemy. Conversely its possible that the radical successes of Ptolemy negated the affects of Galatia’s peace terms with the Seleucids.
Whatever the case is Galatia is firmly established as a political entity as of 272 BC. With clear world objectives in and out of Asia. The remaining questions are
1 Byzantion may very possibly still be a tribute paying state of Leonorius and Loutorius’ Galatians. Whether this means that they are a type 3 government or just flat out paid a large sum of cash I can not verify.
2. What is the exact manner of the relationship between the Volcae Tectosages, dominant shareholders of the Galatian tetrarchy and their brethren in Tolosa.
3. How close politically are the Galatians to Comontorios of Tylis and Bathanatos of the Scordisci.
EDIT::
If anyone has answers to the questions I’ve posed or otherwise objects id like to know. There seem to be a few unfortunate blank spaces, particularly regarding the fates of Leonorius and Loutorius.
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