本研究嘗試透過地圖操作，以及整合歷史學、地理學及族譜等文獻的分析，梳理多數臺灣饒平裔家族之原鄉－元歌都（饒北地區）的歷史區域特色，並嘗試解析元歌都地域進入漢文化區的時程。具體操作上，利用族譜對比、整合元歌都相關姓氏所載入墾年代地史料及所使用方言等資訊，以釐清饒北地區宗族的歷史地理脈絡。利用閩、客式地名，作為劃分饒平閩、客歷史方言區界線的操作型定義，以釐清饒平裔宗族在清代渡臺之初的閩、客族群屬性的歸屬。比較饒平閩、客歷史方言界線與現今饒平方言界線發現，這兩條方言界線相去不遠，在研究實務上顯示，本研究所設計的歷史方言界線具有很好的參考價值。此外，研究發現在饒北地區，某些宗族以「寧化石壁」作為祖居地的說詞，可能是虛構的宗族遷徙史；也就是說，以「寧化石壁」作為辨識客家的指標，必須針對個別宗族的情況逐一檢核，方可確定。

The study tries to use analysis of the maps, and integrates the informations of historical, geographical and genealogical literatures to display regional characteristics of the ancestral home of Taiwan Raoping offspring: the Yuan'ge Du region (The Northern Raoping region). And also attempts to inquiry the time of the Yuan'ge Du region how to shift into Han's region. The research methods of the study include: firstly, we integrate the information about reclamations, dialects, literatures to discover the contexts of historical geography in the Yuan'ge Du region. Secondly, we choose the Southern Min and Hakka place names of Raoping County to target the historcial dialect boundary between Southern Min and Hakka. Thirdly, we put the ancestral homes of Taiwan Raoping's clans into the map of the boundary of Southern Min and Hakka to differentiate the Raoping's clans who should be defined to Southern Min or Hakka. To compare the Raoping historcial dialect boundary between Southern Min and Hakka with the Raoping dialect boundary of today, we found not far from the boundaries in two times. In research practice shows that the historical dialect boundary dialect has a good reference value. In addition, the study found in the northern Raoping region, certain clans to ＂the Ninghua/Shibi＂ as the ancestral home of the rhetoric may be fictional clans migration history. That is, in order to ＂the Ninghua/ Shibi＂ as the identification of Hakka fingerprint must ascertain for each view of individual clans and verification.