In brief, there is disagreement among historical analysts as to the exact time period when the minority leadership emerged officially as a party position. Nonetheless, it seems safe to conclude that the position emerged during the latter part of the 19th century, a period of strong party organization and professional politicians. This era was "marked by strong partisan attachments, resilient patronage-based party organizations, and...high levels of party voting in Congress." Plainly, these were conditions conducive to the establishment of a more highly differentiated House leadership structure.