The Walls of Constantinople
are a series of stone walls that have surrounded and protected the city of Constantinople
since its founding as the capital of the Eastern Roman Empire
by Constantine the Great
. With numerous additions and modifications during their history, they are one of the greatest and most complex fortification
systems ever built. The impression made by the mighty walls on the crusaders who encountered them can be seen in the 13th century Caernarfon Castle
in Wales, built by Edward I of England
as a royal residence, which is said to have been modelled on them.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, when well manned, they were almost impregnable for any medieval besieger, saving the city, and the Byzantine Empire with it, during sieges from the Avars, Arabs, Rus', and Bulgars, among others (see Sieges of Constantinople). With the advent of siege cannons, however, the fortifications became obsolete, but their massive size still provided effective defence, as demonstrated during the Second Ottoman Siege in 1422. In the final siege, which led to the fall of the city to the Ottomans in 1453, the defenders, severely outnumbered, still managed to repeatedly counter Turkish attempts at undermining the walls, repulse several frontal attacks, and restore the damage from the siege cannons for almost two months. Finally, on 29 May, the decisive attack was launched, and when the Genoese general Giovanni Giustiniani was wounded and withdrew, causing a panic among the defenders, the walls were taken. After the capture of the city, Mehmed had the walls repaired in short order among other massive public works projects, and they were kept in repair during the first centuries of Ottoman rule.
The walls were largely maintained intact during most of the Ottoman period, until sections began to be dismantled in the 19th century, as the city outgrew its medieval boundaries. Despite the subsequent lack of maintenance, many parts of the walls survived and are still standing today. A large-scale restoration programme has been under way in the past twenty years, which allows the visitor to appreciate their original appearance.
[[Image:|center|420px|Battle of Diu (1509)]]
The Battle of Diu sometimes referred as the Second Battle of Chaul was a naval battle fought on February 3, 1509 in the Arabian Sea, near the port of Diu, India, between the Portuguese Empire and a joint fleet of the Mamlûk Burji Sultanate of Egypt, the Ottoman Empire, the Zamorin of Calicut and the Sultan of Gujarat, with technical naval support from the Republic of Venice and the Republic of Ragusa (Dubrovnik). The Portuguese victory was critical for its strategy of control of the Indian Ocean, setting its trade dominance for almost a century, and thus greatly assisted the growth of the Portuguese Empire. It marks also the beginning of the European colonial dominance in Asia. It also marks the spillover of the Christian-Islamic power struggle, in Europe and the Middle East, into the Indian Ocean which was the dominant region of international trade at that time.
After this battle, the Portuguese rapidly captured key ports and coastal areas in the Indian Ocean like Goa, Ceylon, Malacca and Ormuz. This allowed them to circumvent the traditional spice route controlled by the Arabs and the Venetians, and by routing the trade down the Cape of Good Hope, they simultaneously crippled the Mamluk Sultanate of Egypt and the Gujarat Sultanate. The Portuguese sea monopoly lasted until it was taken during the Dutch-Portuguese War, the British East India Company and the Battle of Swally in 1612.