The banner of the Prophet (saas) will be unfurled by the Mahdi

The flag and ensign are one of a society's most important symbols.
Both symbolize that community, from the smallest unit to the largest.
There is one flag whose significance and importance distinguish it
from others. This is theBanner of the Prophet (saas), a legacy from
our Prophet Muhammad (saas) known as "Uqab" (The Eagle). It has been
asymbol of Islam for the past 1400 years. The Prophet (saas) always
went into battle with Uqab.
For Arab tribes, the banner falling to the ground meant defeat. In the
event of such a disaster, the troops would accept their defeat and
flee. For that reason, when the ensign-bearer was wounded or died, the
next person in line to carry it was determined before the battle even
begun, far in advance, and he would immediately take chargeof it in
the event that this happened to the ensign-bearer.
Our Prophet (saas) commanded that all the flags to be used should be
white. However, Uqab was black. Anotherdifference between this ensign
and others was that it was made of a woolen fabric.
Prior to Islam, this flag, used by the Quraish tribes was of a
unifying importance for all Arabs. All the tribes, at that time,
united under this banner during the spread of Islam. Apart from this
banner of our Prophet's (saas), there were many other flags belonging
to the army, but Uqab was specific to the office of
commander-in-chief. Following the spread of Islam and the death of our
Prophet (saas), the four caliphs took over this sacred relic.
According to official records, this ensign was transferred to the
Umayyad and Abbasid caliphs, and after the capture of Baghdad by the
Mongols it was takento Egypt by the Abbasid caliph. Uqab then
passedinto the hands of the Ottomans with the conquest of Egypt by
Sultan Selim the Stern. On his return from Egypt the sultan carried
the ensign to Istanbul, where it has been ever since.
After the Banner of the Prophet (saas) passed into the hands of the
Ottomans, it was carried into battle by them as a custom. Shortly
before the army descended onto the battlefield the Banner of the
Prophet (saas) would be taken out and preparations would be made. The
ensign was taken to the field of battle in its coverand defended by
ensign-bearers. The presence with the army of the Banner of the
Prophet (saas) was regarded as an enormous honor.
The Ottoman Empire, itself the ensign-bearer of Islamic moral values
for centuries, attained a great honor with the arrival of the Banner
of the Prophet (saas) to Istanbul.
The ensign Uqab, which once belonged to our Prophet (saas), is also,
in addition to this feature, a sign and a herald of a most important
matter. Our Prophet (saas) has reported that when the Banner of the
Prophet (saas) is unfurled, this will be a sign of the end times, a
period in which people will live by the moral values of the Qur'an. We
are told in hadiths that:
It is related from Abdullah ibn Shurafa that: The banner of our
Prophet (saas) will be adorned, together with the Mahdi. (Al-Burhan fi
Alamat al-Mahdi Akhir al-zaman, p. 65)
He will appear with the camel hair banner of our Prophet (saas). That
banner has four corners,is unstitched and black in color. There is a
halo on it. It has not been unfurled since the death of our Prophet
(saas), but it will be opened when the Mahdi appears. (Al-Burhan fi
Alamat al-Mahdi Akhir al-zaman, p. 23)
As for signs, he will have with him the shirt, the sword, and the
banner of our Prophet (saas). That banner has never been unfurled
since the death of our Prophet (saas). And, it will not be unfurled
until the appearance of the Mahdi. (Portents of Doomsday, p. 164)
The Mahdi will appear with the banner of our Prophet (saas). That
banner is unstitched, black, and has four corners. It has never been
unfurled since the death of our Prophet (saas) but will be unfurled by
the Mahdi. (The Book of Portents of the Awaited Mahdi, pp. 41-41, 52,
54)
The banner, the color, shape, and stitching of which are described in
the hadiths of our Prophet (saas), is today housed in the Sacred
Relics Department at Topkapi Palace.
One important feature ofthis banner, which we are told will only be
unfurled by the Mahdi inthe end times, is that "it has never been
unfurled since the death of our Prophet (saas)." According to
historical sources, the banner has never been opened by any state,
including the Ottoman Empire, out of respect for the Prophet (saas),
and was never taken out of its cover even during the battles or during
the ceremonies it was taken to. The banner, preserved in this way
for1400 years, will be unfurled in the end times, when Islamic moral
values will prevail,with the coming of the Mahdi. (Allah knows the
truth.)
A ceremony at which theBanner of the Prophet (saas) was suspended from
this wall would be held at the Gate of Happiness.
The Gate of Happiness (The Gate of the White Eunuchs) to which the
Banner of the Prophet (saas) was attached to send the army off in
times of war.
The army took the Banner of the Prophet (saas) with them upon
departing for the Egri War, and this provided with enormous fervor and
motivation.