sentences:  Its capital was Kutaraja, the present-day Banda Aceh.At its peak it was a formidable enemy of the Sultanate of Johor and Portuguese-controlled Malacca, both on the Malayan Peninsula, as all three attempted to control the trade through the Strait of Malacca and the regional exports of pepper and tin with fluctuating success.In addition to its considerable military strength, the court of Aceh became a noted centre of Islamic scholarship and trade.