In 285 AD Diocletian conceived a scheme for the governance of the much-extended Roman Empire which he hoped would obliterate struggles for power by usurpation and, at the same time, share out the increased work-load. A ruler (an Augustus: Diocletian himself) was to be appointed for the East, with his capital at Nicomedia; and another for the West (Maximian); each was to have an understudy (a Caesar), who would eventually take over, having learned "on the job" by understudying his superior. Diocletian entered into the spirit of the scheme by actually resigning his Emperorship:

"The ceremony of his abdication was performed in a spacious plain, about three miles from Nicomedia. The emperor ascended a lofty throne, and, in a speech full of reason and dignity, declared his intention, both to the people and to the soldiers who were assembled on this extraordinary occasion. As soon as he had divested himself of the purple, he withdrew from the gazing multitude, and, traversing the city in a covered chariot, proceeded without delay to the favourite retirement which he had chosen in his native country of Dalmatia" (Gibbon 1960, 133-4). Maximian also retired, apparently to a villa in Lucania.

Here are the four tetrarchs, represented in porphyry on the sea-facing corner of the facade of S. Mark's, Venice - presumably stolen from Constantinople during the terrible sack of that city in 1204:

But the system did not work, wrecked on the traditional shoals of dynastic struggle and power-seeking. Maximian asked Diocletian to resume the reins of office and the Imperial purple, but "he rejected the temptation with a smile of pity, calmly observing that, if he could show Maximian the cabbages which he had planted with his own hands at Salona, he should no longer be urged to relinquish the enjoyment of happiness for the pursuit of power" (Gibbon 1960, 134);

From here you may go to any of the following screens:

The Introductory Page; The Colonnaded Streets; Comparisons with Split's Architecture; Diocletian as Builder; The Emperor's Apartments; The Great Hall & Peristyle Complex; The Emperor's Mausoleum; Is Split palace or chateau?; The Temple; The Walls & Gates The Bibliography; My Biography; The technology I've used; A Short Research Paper.