The main reason Aceh is not Indonesia is because Aceh existed long before Indonesia emerged, this can be evidenced from various historical views, which prove it. Indonesia emerged since 1945, but not with Aceh, which has emerged hundreds of years ago, with hundreds of leaders we call the sultan.
The Sultanate of Aceh, officially the Kingdom of Aceh Darussalam (Acehnese: Keurajeuën Acèh Darussalam; Jawoë: كاورجاون اچيه دارالسلام), was a Sultanate centred in the modern-day Indonesian province of Aceh. It was a major regional power in the 16th and 17th centuries, before experiencing a long period of decline.
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. wikipedia
Another reason why Aceh is not Indonesia is from the language used today in the archipelago is the Malay language of Aceh,
This Malay language is also associated with a Buddhist-style kingdom that once emerged in the southern region of Sumatra, the Sriwijaya Kingdom. Therefore, they also concluded that the ancient Malay inscriptions found in the southern region of Sumatra originated from the period before the emergence of Islamic empires.
As for the oldest inscriptions in ancient Malay language made in the Islamic era and still using ancient Sumatra script, the experts agreed to design an inscription on a tombstone located in Gampong Menye Tujoeh, East Pirak District, North Aceh Regency, Aceh Province. This is evidenced by the abundance of scientific research, with the findings of archaeologists.
Read : http://www.mapesaaceh.com/2015/11/malaysia-brunei-darussalam-dan.html
Flag of Aceh
Even long before Indonesia's independence, The archipelago under the sultanate of Aceh Darussalam, except Melaka and Singapore.
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