In the following year, the Secret Garden was formed on the north of Changdeokgung Palace and was expanded in 1463 (the 9th year of King Sejo) to blend in the space of governance and residence. Changdeokgung Palace was destroyed in the Japanese invasion in 1592 (the 25th year of King Seonjo) and rebuilt in 1610 (the 2nd year of King Gwanghaegun) before any other palaces. It was the major residence of kings for the next 270 years until Gyeongbokgung Palace was rebuilt in 1867 and served as the de facto primary palace. From the age of King Injo to King Sunjo, more structures such as Ongnyucheon Stream, Gyujanggak Library, Juhamnu Pavilion, Aeryeonji Pond, Uiduhap Study Area, and Yeongyeongdang Complex were constructed within the palace premises. In 1847 (the 13th year of King Heonjong), the Nakseonjae area was established, further expanding the grounds of the palace.
Changdeokgung Palace was often called Donggwol, or the East Palace, and had no boundaries that separated it from Changgyeonggung Palace. It was built in harmony with the surroundings and is regarded as the most Korean-style palace.
In particular, Emperor Sunjong (r. 1907–1910), the second emperor of the Korean Empire, resided in Changdeokgung Palace after his ascension to the throne and passed away here. Heungbokheon, a subsidiary building of Daejojeon Hall, is also the tragic place where the Korea–Japan Treaty of 1910 was signed. Changdeokgung Palace is also where the last descendants of the royal family (Empress Sunjeong, the second queen of Emperor Sunjong; Crown Princess Yi Bangja; and Princess Deokhye) lived and passed away.