Septimus III
Septimus III was the inhabited third planet in the Septimus system, in the Alpha Quadrant. The headquarters of the Cardassian Eleventh Order was located on this planet. 

The planet was attacked by the Klingon Empire in late 2375, near the end of the Dominion War. The Klingons landed fifteen divisions, wiping out the Eleventh Order. According to Weyoun, this meant the Klingons had expended valuable resources to capture a strategically worthless planet. However, the Klingon victory ended up costing the Dominion heavily nonetheless because the nonchalance of Weyoun sacrificing the 500,000 men strong Eleventh Order was the final indignity that caused Legate Damar to instigate the Cardassian Rebellion. ()

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Septimus 03