When Osman Ghazi died in 1323, he left two sons, one of whom would take on the role of continuing Osman's work in creating the Ottoman Empire. There are plenty of examples of princes fighting with each other over the succession, but that did not happen in this case. Prince Orhan became the natural leader, but his brother provided valuable aid.
Alaeddin Erden Ali Pasha (c 1281 - 1331) not only did not clash with Orhan (some scholars think Alaeddin may even have been the elder of the two), but he supported his brother with ideas and projects that advanced the cause of the Ottomans in ways that mere military conquest would not.
There are three innovations for which Alaeddin gets credit during this period, while Orhan led the military and held the title of sultan. It was after a particular conquest in 1328 that Alaeddin visited his brother to congratulate him and to make three suggestions.
The first was to establish their own monetary system to enhance trade and add an air of legitimacy and independence to the Ottomans. Silver coins dating to that year have Orhan's name on one side and "May Allah make his reign eternal" on the other (see illustration).
His next suggestion was to distinguish Orhan's Ottomans from other Turks and Muslims by developing distinctive style of dress. Inspired by the Byzantines, Ottoman government and military officials took on specific clothing styles. Also, based on an Arabic saying that 'the best garment is a white one,' everyday wear was suggested to include a simple white cap to distinguish followers from non-Ottomans.
Alaeddin's most significant contribution may have been in Orhan's wheelhouse: the military. Rather than the previous method of a leader trying to maneuver a vast array of men to do his bidding, the army was divided into separate contingents, each with its own leader who would report to and gain orders from higher up. This hierarchical style of military affairs is so efficient and common that it is difficult to believe that it was not always the case, but charismatic and successful (and unsuccessful) leaders did not always delegate.
Part of the military re-organization involved designating citizens as foot soldiers who could be called up when necessary. Since they had no formal training, however, they were ineffective. Decades after Alaeddin's failed idea, however, something vaguely similar was proposed. Tomorrow I'll tell you the horrifying story of the Janissaries.