Two years ago this week, the Islamic State overran the Iraqi city of Mosul in a humiliating defeat for the country's U.S.-trained security forces. Hundreds of thousands of terrified civilians and soldiers fled the city as the militants swiftly advanced.

Appearing at a mosque in Mosul later in June 2014, the leader of the Islamic State, Abu Bakr al-Baghdadi, declared the creation of a caliphate. His militants had claimed about a third of Iraq's territory.

Today, the Islamic State is a much diminished force as it suffers a string of battlefield losses backed by U.S.-led airstrikes in Iraq, while Syrian rebels and President Bashar al-Assad's forces have been fighting it in Syria. Officials estimate that the militants have lost 45 percent of the territory it once had in Iraq and 20 percent in Syria.

But Mosul, which once had a population of nearly 1.5 million,  remains under Islamic State control.

Here's a look at the territory the group has lost in both countries this year.

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