Just before 1880, Leopold II wanted to develop this area of Brussels by creating a sort of " Sorbonne Area " crowned by a Pantheon dedicated to Great Belgians and perhaps a sepulchre for these celebrated people.

The King dropped this project for lack of support and, wanting to celebrate the 75th anniversary of the country's independence, thought of the construction of a national sanctuary consecrated to the Sacred- Heart, comparable to the Basilica of Montmartre. Fascinated by Paris, the townplanner King wanted to create at Koekelberg a Basilica situated at the centre of a " Star " of avenues with its own " Champs Elysées " leading into the capital.

On 12th October 1905, Leopold II laid the foundation stone of the building; the initial project, by the Leuven architect Langerock, was for a sumptuous temple in 13th century French Gothic style.

Only the foundations had been finished when the First World War broke out. In his pastoral letter at Christmas 1914, Cardinal Mercier gave the Basilica a new meaning: " As soon as Peace shines forth once more upon our land, we will raise up our ruins and we hope to put the crown on this work of reconstruction by building the National Basilica of the Sacred Heart on the heights of the capital of free and catholic Belgium ".

On 29th June 1919 King Albert I, national personalities and a large crowd associated themselves  with  this promise in a ceremony on the Plateau of Koekelberg. However there could be no question of resuming Langerock's plan because of the state of public finances.

A project by architect Albert Van Huffel was adopted. A plaster maquette, to the scale of a fortieth, was made and shown among others at the " Exposition des Arts Décoratifs " in Paris in 1925.
Since then, by stages, the monument you are standing in was built up thanks to the care of the promotor and, after his death, on I6th March 1935, of architect-engineer Paul Rome, his collaborator and associate (┼ June 1989).

The adaptation and extension of the existing foundations were undertaken from January 1926.
The construction company began building the apse in August 1930; this was blessed on 26th May 1935 and worship could begin. The base of the dome was finished when in 1940 the Second World War brought a new halt to the works. Building resumed since September 1944, the main nave was finished in 1951, when the two towers had reached a height of 45 metres.

Nothing of an essential nature was lacking when on 13th and 14th October 1951 Cardinal Van Roey presided over the imposing consecration ceremonies for this Minor Basilica, a title granted by Pope Pius XII on 28th January 1952.
Both towers were finished in 1953, the south transept opened in 1958 and the north transept in 1962.

The cupola was finished in 1969 and, on 11th November 1970, the ceremony for the 25th anniversary of the episcopate of Cardinal Suenens, Archbishop of Mechelen-Brussels, marked the completion of the construction of the Basilica.