It's Federation Day!
It's Federation Day! was the title of a newspaper clipping created as background material for  by Larry Nemecek. The clipping was placed in the Picard family album. 

Although the album was featured prominently in the film, the clipping itself was not seen on screen and is therefore not canon. Names and other details from the clipping were used by author David A. Goodman in his reference book Star Trek: Federation - The First 150 Years.

According to the clipping, the initial article was distributed by the Solar News Network on October 11, 2161. The article's text chronicled the events of the founding of the United Federation of Planets, the anniversary of which became known as "Federation Day", as suggested by the reference to Federation Day poker in the  fifth season episode . Below is a copy of the text.

SOLAR NEWS NETWORK HARD COPY EXTRACT      10.11.2161

IT'S FEDERATION DAY!
5 sign new UFP Constitution
SAN FRANCISCO, Earth (SNN) – Declaring it a landmark day in the history of each of their worlds, five envoys today breathed life into the fledgling United Federation of Planets with the signing of the new organization's Constitution amid much pomp and circumstance.
"We are truly entering a brave new world of peace, exploration and security with the establishment of this Federation, declared Earth ambassador Thomas Vanderbilt, whose remarks were echoed by representatives from , Andor, Tellar, and Alpha Centauri.
"Following the end of your world's war with the unseen Romulan enemy, such a union as we create here today is the most logical course of action any of our peoples can take," added Ambassador T'Jan of Vulcan.
UESPA Maj. Gen. Georges E. Picard, an aide to Vanderbilt, noted afterward the irony of the conference – which met in exactly the same fashion as the founders of the Earth's old United Nations, who came together only 215 years earlier in the same city in the aftermath of the horrors of another costly war.*
"What is occurring here today is one sign that some good can come of such a scourge," Picard noted.
"We defy anyone, even the Romulans, to test our resolve now for collective security," declared Ambassador Natha Kell of Tellar, while Sarahd of Andor spoke of future greatness for the infant union and predicted rapid expansion. Ambassador Titus Oleet signed for the newly independent Centauri system.
Today's events were but the ceremonial endgame for the often-tumultuous negotiations, which began in earnest after the defeat of hostile forces at Cheron effectively ended the Romulan War only a little more than a year ago. Even today, some sources reported a later fracas involving the Tellarite Kell and Sarahd.
Although those taking part today waived off revealing many specific details, the five after signing immediately convened the first-ever meeting of the UFP Council long enough to elect Vanderbilt as president, with Sarahd as vice president.
Also, the Council sources unanimously voted to continue meeting in San Francisco, with an all-new building in the design stages near the historic old Presidio fort and Golden Gate Bridge. Council sources predicted at least three months would be needed before the fledgling UFP bureaucracy would be ready for business.

* This is an error: the UN was founded in 1945, which would be 216 years prior to the founding of the Federation, not 215 years.

fr:It's Federation Day!
Unused production material