The national territory of the Philippines was expanded through presidential decrees, which were significant during the time of Ferdinand Marcos Sr.
When he declared martial law on September 21, 1972, he didn’t need Congress to pass laws; he could do it himself.
Marcos Sr. shifted to a parliamentary system as part of his strategy to consolidate power under the 1973 Constitution.
In effect, he acted as both president and lawmaker.
That gave him the power to set territorial boundaries and national policies through official orders called presidential decrees.
National Territory of the Philippines According to Presidential Decrees
During martial law, Marcos Sr. issued presidential decrees that directly addressed the national territory of the Philippines.
While the constitution at the time gave a general definition of the national territory, the decrees were more specific.
They named actual areas, groups of islands, and sea zones that the Philippines claimed. Let us discuss them below.

Presidential Decree No. 1596: Kalayaan Island Group
Marcos Sr. issued Presidential Decree No. 1596 on June 11, 1978, which declared the Kalayaan Island Group as belonging to the Philippines.
He created the Municipality of Kalayaan under the province of Palawan.
Before it was claimed, the Kalayaan Island Group was known as the “Free Territory of Freedomland,” a cluster of uninhabited islets in the South China Sea.
It was rich in natural resources and located along major international shipping routes, so the government saw it as valuable.
Presidential Decree No. 1599: Exclusive Economic Zone
Marcos Sr. also issued Presidential Decree No. 1599 on June 11, 1978.
This established the Philippines’ Exclusive Economic Zone, extending up to 200 nautical miles from its baselines.
Within this zone, Filipinos have the sovereign right to explore, exploit, conserve, and manage natural resources.
This includes fishing, oil exploration, and mineral extraction.

Ferdinand Marcos Sr. Signed Proclamation No. 370 Before the Martial Law
Marcos Sr. signed Proclamation No. 370 on March 20, 1968. The government at the time was operating under a democratic setup.
Proclamation No. 370 stated that all natural resources in the continental shelf adjacent to the Philippines were open for Philippine exploration and use.
This set the stage for Presidential Decree No. 1596, which made the Kalayaan Island Group officially part of Philippine territory.








