History
The Ottoman Empire was named after its founder Osman I, who led a small Oghuz Turkish kingdom in western Anatolia after the fall of the Seljuq Empire. In the 14th century it rapidly expanded in the Balkans at the cost of the Byzantine Empire and the kingdoms of Bulgaria and Serbia.
The biggest turning point was in 1453, when Ottoman forces captured the Byzantine capital of Constantinople, and turned it into the capital of the Ottoman Empire. Ever since the Russians have seen themselves as the guarantor of the Greek Church, which fueled Russian expansionism from the 17th century up to the fall of the Ottoman Empire in 1922. In the 16th and 17th century, including the reign of Suleyman the Magnificent, the Ottomans Empire reached its largest extent. It conquered Egypt in 1515 and in 1529 and 1683 Ottoman forces were at the gates of Vienna. 1683 marked the start of decline when a European alliance of the Holy Roman Empire, Poland and Russia defeated the Ottomans in multiple battles up to 1693. Subsequently, European advances in technology outpaced the Ottomans which led to the gradual decline of the Ottoman Empire.

Ottoman Empire in 1683
The following centuries, especially starting from the 19th, vast territories of the Ottoman Empire were lost either by conquest or by local uprisings, often supported by neighbouring powers. These losses frustrated many Turks who were drawn to nationalist groups such as the Young Turks movement that led to a revolution in 1908, and whose ideologies stood at the basis of large-scale ethnic cleansing in the early 20th century.
By the start of WW1 the Ottoman Empire was reduced to modern-day Turkey, the Levant, Palestine and the Arabian peninsula. The Ottomans joined the Central Powers in WW1 which led to a Caucasus front with Russia and a failed invasion by British and ANZAC troops in Gallipoli, a battle which was won by the Ottomans but at the cost of half a million lives. The Ottomans faced a Russian advance in Western Armenia and British-supported Arab uprisings in Mesopotamia. Palestine was lost to the British in 1917.
The Ottoman Empire collapsed at the end of the war, except on the eastern front because Russia had left the war after the Bolshevist takeover in the October Revolution. The result was a fierce Ottoman campaign against Armenians which had supported the Russians during the war in the hope of establishing an independent state. The Armenians had already suffered from massacres by the Ottomans 20 years before, but the campaign of 1916 was on an unprecedented scale. More than a million Armenians died and another 300,000 Christian Assyrians in what was an example of large scale ethnic cleansing that had gone relatively unnoticed by the outside world. This course of events is still a very sensitive issue in Turkey, where it is seen as a consequence of war rather than an operation targeted at removing all Armenians and Assyrians from Anatolia.
By 1918 Constantinople (present-day Istanbul) was occupied by the British and the 1920 Treaty of Sèvres organised the partition of the Ottoman Empire with Turkish lands greatly reduced. It was Mustafa Kemal Ataturk who led an uprising in the Turkish War of Independence that made most of the 1920 partitions undone. In 1922 the last sultan abdicated and a year later the Republic of Turkey was established.
Currency
The Ottoman Empire initially used the Akçe as the main unit, a coin of approx. 1.15 grams of silver. It was first struck in the 14th century. Copper coins named Mangır (meaning dough) also circulated but its value fluctuated (it is mentioned that 24 small Mangır = 1 Akçe). In later centuries the Akçe was debased many times until it ceased to be struck in the 18th century. In 1687 the Kuruş became the main unit of account, worth 40 Para or 120 Akçe. The Kuruş is derived from French Gros and German Groschen, and weighed around 27 grams in silver. Also this coin was debased over time, dropping to 4.65 grams by 1810 and 1 gram by 1900. Other units that existed were the Zolota (3/4 Kuruş) and Yirmilik (1/2 Kuruş).
Separate gold coinage existed in the form of the Altın (equal to the Venetian Ducat, 3.45 grams of gold). Altın is the Turkish word for gold. It was worth 6 Kuruş but as the latter lost value due to inflation the rate fluctuated. The Altın was later replaced by the Zeri Mahbub of 2.6 grams of gold, equal to 3.5 Kuruş.
In 1843, the Lira was introduced at a rate of 100 Kuruş, and put on a gold standard making it worth around 1.1 Lira per British Pound Sterling. The old system of 40 Para = 1 Kuruş stayed in place but the Akçe ceased to exist due to its low value. The Lira remained on a gold standard until the outbreak of WW1 in 1914. In 1923 the Republic of Turkey was proclaimed which kept the Lira as its currency, though debased to 10 Lira/£, 9 times less than before the war.
The North African parts of the Ottoman Empire used its own coinage. Algeria, Tunis, Tripolitania and Egypt all had their own coins during the Ottoman era.
Coins
Ottoman coin history goes back centuries and most pre-1800 coins hardly ever show up in auctions unless you look for them very specifically. Machine struck coins from the 1850's and later are pretty common, some of which can even be found at bargain bin prices.
The most striking feature of Ottoman coins is the Tughra, the calligraphic symbol on most Ottoman coins, including the Egyptian ones. The Tughra was the signature of the Sultan and bore the name of the Sultan in combination with symbolic features. Although they all look very alike to the untrained eye, look at the bottom to see the name of the Sultan.

Above a schematic outline of the Tughra. The Sultan's name is written at the 'Sere'. The 'Tuğ' represents flagstaffs, symbolising independence. The 'Hançer' signifies a sword, a symbol of power.
https://en.numista.com/catalogue/ottoman-1.html














