The Athens Academy aims to shed light on a decisive chapter of Byzantine and Eastern Mediterranean history this week, with a conference on the Fourth Crusade. Marking 800 years from the Fourth Crusade, the international conference, which begins at the Academy’s premises today, is sponsored by the I.F. Costopoulos Foundation. In 1202, an army of Crusaders gathered in Venice in the hopes of regaining the Holy Land from the Muslims. Soon the target was abandoned and replaced, with troops marching toward Constantinople, in the presence of the deposed heir of the Byzantine kingdom; the latter had asked his western allies for help, thus presenting a motive for the offensive. Even though the coalition did not bear fruit, Constantinople was conquered by the Crusaders and the Venetians on April 13, 1204. The consequences were substantial for the entire region and the future of the Byzantine Empire – the most noteworthy being the splintering of the geographical and political area of the Byzantine state into Greek or western miniature states. It is these consequences which leading scientists are called to examine this week, by presenting a series of issues. The conference opens with a keynote speech on the Fourth Crusade as an institution by Professor Jonathan Riley-Smith at 7 p.m. Greek President Costis Stephanopoulos is scheduled to attend tonight’s opening session. Also on the conference agenda are the relationships between the churches since the 13th century as well as developments and changes in the economy, architecture and the arts both in Constantinople and the broader region. Athens Academy, Academias & Sina, tel 210.366.4733. To Friday.