Our Malaysian flag was given the name Jalur Gemilang on 31st August 1997, the 40th anniversary of our independence.
There are some people who think that like Negaraku, Jalur Gemilang was a copycat of the American flag. I have doubts. I shall dwell on this another time.
However, one thing that is interesting to note is that when this flag was first designed and meanings given, dark blue symbolised connexion with the Commonwealth. Later, during Mahathir's regime, in his nationalistic ideology, the colour dark blue is to symbolise 'perpaduan' or unity of the people of Malaysia.
Yes, the dark blue in Jalur Gemilang symbolises Malaysian Unity! Yes, our national flag, Jalur Gemilang emphasises Malaysian Unity!
50 going on 51. Will we rise up together and achieve Malaysian Unity rather than to continue dividing the people?
Update: Malaysia Government 's Official Portal: The canton of dark blue in the upper quarter next to the staff and extending down to the top of the fifth stripe stands for the unity of the people of Malaysia. The union contains a crescent which symbolises Islam, the official religion of Malaysia.