Ghaza thesis
The Ghaza or Ghazi thesis (from Ottoman Turkish: غزا, ġazā, "holy war", or simply "raid") is a since disputed historical paradigm first formulated by Paul Wittek which has been used to interpret the nature of the Ottoman Empire during the earliest period of its history, the fourteenth century, and its subsequent history. The thesis addresses the question of how the Ottomans were able to expand from a small principality on the frontier of the Byzantine Empire into a centralized, intercontinental empire.