Complex sentence: The Imperial colours Black and Gold were adopted by many Imperial cities to underline their immediacy; when the last Habsburg emperor Francis II abdicated from the throne in 1806, he adopted the colours as the flag of his Austrian Empire.
Split into simpler sentences: The Imperial colours Black and Gold were adopted by many Imperial cities to underline their immediacy. When the last Habsburg emperor Francis II abdicated from the throne in 1806, he adopted the colours as the flag of his Austrian Empire.