Ggtkuk

In this web page, a photo from a repertory of photos from the Spanish Civil War, at the website of the archive of Italian Istituto Luce, shows a rally with Francisco Franco within a theatre. From the balconies several flags hang, among which are the German and the Italian ones, and then one with what seems a light-coloured Star of David on a darker background.

Image source: Istituto Luce / Archivo Luce

Does anyone know whose nation or organisation was this flag, and why it was shown at a Francoist meeting?

Q Why does a Star of David appear at a rally with Francisco Franco?

1. Because the symbol was much more ambiguous at the time, and not a one-to-one signifier of "Jewishness".


2. Because Franco had his base in Northern Africa, Morocco, and the symbol represents this early power base, just as the other flags show where his support came from.

Most probably because this is not really a star of David, but a hexagram. As such it has probably less to do with Jews, Zionists or Israel being a part of Franco's movement or even on the guest list for this occasion.

Whether this is an occult symbol, popular with fascists, or a stylised version of an etoile, six pointed star or estrella de seis puntas, the basic pattern is widespread and used in heraldry for cities, where this meeting could have taken place.

Example for six-points (plus: no connection to Islam, despite the crescent) Armañanzas

Example for a Spanish nationalist or falange fighter, no connection to Jewish symbolism:

(src)

That said, in this case it might simply be a reminder of the glorious origins of the falangist forces of Franco. And that is in North-Africa. The Spanish Protectorate of Morocco sported this type of flag in various variations:

Flag of Morocco in early 20th century

Source: WP List of Moroccan flags

Just like in a French encyclopaedia, copyright 1923.

But compare the apparently argent variant with Spanish Protectorate of Morocco (1912-1956) and

The symbol of armed authority was a hexagram … Starting from the reign of the Sultans Hisham (1790/’92-’97) and Suleyman (1792-1822) the hexagram is uninterruptedly documented on coins until 1956.

But if that sounds still like a tough sell to Catholic Spanish falangistas, either something looking like a Jewish or a Moroccan symbol, then it might be as well recognising a symbol of Mary or stella maris:

Just like the Star of David, the Star of Mary is a Six-Pointed Hexagram

(a)
(b)

(a) A 13th century Church in Asturias, Spain known as 'Iglesia de Santa María' (1270 A.D.)

Among the medas and insignia used in connection to the Army of Africa, the Order of the Medhauia seems to stick out:

To reward those very distinguished and notorious facts of Spaniards and Moroccans carried out in the Zone of Morocco entrusted to the Protectorate of Spain.
(a) (b)
<sub>(a) Rifaat (equivalent to gentleman)
Visirial decree of 8 of safar of 1345 -18 August 1926-
Award period: 1926-1956
Compose the central part of the badge of an enameled circle, in which the setting Sun is represented, that is to say "The Mogreb", reflected in a blue-green sea. Circumscribed to this circle is a strip, also of enamel and of Prussian blue color, limited by a golden fillet. Everything described above is enclosed in a Solomonic ring.
The ribbon on which the decoration hangs is green, with a white central stripe.

On the back, in a circle of white enamel, read the following Arabic inscription: "Muley el Mehdi Ben Ismail Ben Mohamed, glorify him God"
Both the Solomonic ring and the ornaments will be silver. It is suspended from the left side of the chest

(b) Sumú-u (equivalent to the Great Cross)
Visirial decree of 8 of safar of 1345–18 August 1926-
Award period: 1926-1956
Compose the central part of the badge of an enameled circle, in which the setting Sun is represented, that is to say "The Mogreb", reflected in a blue-green sea. Circumscribed to this circle is a strip, also of enamel and of Prussian blue color, limited by a golden fillet. Everything described above is enclosed in a Solomonic ring.
On the back, in a circle of white enamel, read the following Arabic inscription: "Muley el Mehdi Ben Ismail Ben Mohamed, glorify him God"
Identical to the previous one and attached to the left side, taking, in addition, a band that crosses the chest from right to left and from whose end the second class badge hangs</sub>

And further campaign militaria offered by wwwmilitariabcncom:

Nationalist Army… Spanish Civil War.

(a)
(b)

(a) Army badge Moroccan Army Corps. 92 Division. Nationalist Army. Spanish Civil War.

(b) Collar badge. Supervisor of the Mehala Jalifiana . (Colonial Troops).

And finally, a propaganda poster from that time in colour:

Venus Dictator in Furs. Painting by Paco Ibera

_{Franco in furs like Bette Davis. He wears his Miss España sash in the traditional Spanish colors (as opposed to the red, yellow & purple of the Republican flag) and on his chest is a maltese cross (an order of knighthood perhaps? – this forum leads me to the Grand Cross of the Order of San Fernando). Below the cross is a pin of the symbol of the Falangists. His hand rests on a cane while his other hand holds his hat; a garrison cap with a gold tassel. He tries to strike a regal pose. Franco alone takes up nearly half of the image.}

_{On the lower left is a cartouche with Franco's well known and brief declaration of the end of the Spanish Civil War. In a Roman font it declares in large type "La Guerra ha terminado" (The war is over). There is probably no connection between this and John Lennon's song "War is Over."}

One of the flags in the background is either a pentagram or a hexagram flag of the caliph of Morocco.

Perhaps clearing up some confusion:

WP: Seal of Solomon

The current flag of Morocco, introduced in 1915 (r. Yusef) displays a green pentagram in reference to Solomon.]]The Seal of Solomon (or Ring of Solomon; Arabic: خاتم سليمان‎ Khātam Sulaymān) is the signet ring attributed to King Solomon in medieval Jewish tradition and in Islamic and Western occultism. It was often depicted in either a pentagram or hexagram shape; the latter also known as the Star of David in Jewish tradition.

The difference in modern views about the symbol as such looks sometimes a bit contrived: Understanding the Differences between the Star of David and the Seal of Solomon

But for this application it remains important that the pentagram and hexagram were both used, interchangeably.

Cf Whitney Smith & Ottfried Neubecker: "Wappen und Flaggen aller Nationen", Battenberg: München, 1980 & Georg Eisner: "Vom Hexagramm zum Davidstern" (PDF)

The Seal of Solomon is sometimes a plain pentagram or a hexagram.

H. Henry Spoer: "Arabic Magic Medicinal Bowls", Journal of the American Oriental Society, Vol. 55, No. 3 (Sep., 1935), pp. 237-256.

Although we can't tell the colours from the OP's photo, and although the dimensions are different, circumstantial evidence suggests this may be the flag of the Khalif of Morocco, the puppet ruler who helped Franco's nationalists (see below).

Image source: Flags of the World

The hexagram flag is almost certainly a reference to Spanish Morocco (with which, as noted by LangLangC in his answer, Franco and his forces had a strong connection) and the Army of Africa. The Army of Africa played a key role for Franco's Nationalists during the Spanish Civil War.

These sets of stamps were issued, probably in 1939, with Franco and the hexagram.

FRANCO, VICTORIOSO (VICTORIOUS)

Image source: ebay

FRANCO, CAUDILLO (LEADER)

Image source: ebay

FRANCO, GENERALISSIMO

Image source: ebay

The ebay seller dates them 1937-39, but this flickr comment specifying 1939 seems more likely:

This was issued by Spanish Morocco in 1939 to aid disabled soldiers in
North Africa. On the back the price was una peseta.

For an actual flag, there is this Bandera del Jalifa Protectorado Espanol en Marruecos (1912 - 1956):

Source: elgrancapitan.org

Unfortunately, there is no further information on this image on this page but the same flag is shown on Flags of the World where it is referred to as "the kaliph’s standard". It appears to have first been used in the early 1930s.

With reference to the text "La Bandera del Jalifa" below the flag in this answer, there is this in La Empresa Inacabada

Acabada la guerra, las tropas musulmanas de Marruecos, como
integrantes del ejército victorioso, desfilaron con la bandera del
Jalifa en importantes actos militares

Translation: After the war, the Muslim troops of Morocco, as members of the victorious army, paraded with the flag of the Khalifa in important military acts.

Las banderas del Jalifa also appears in a Jorge Luis Borges story

...de la revision historiado oficial de los Abbasidas, que atribuía
las victorias a las banderas del Jalifa, éste, entre tanto,
sospechosamente habituado a destituir a sus generales...

Translation: ...the official historians review of the Abbasids, who attributed the victories to the flags of the Khalifa, the latter, meanwhile, suspiciously accustomed to dismiss his generals...

Also, The Spanish Civil War 1936–39 (1): Nationalist Forces mentions this specific contribution to the Nationalist cause:

The puppet ruler of the protectorate, the Khalifa, put his put his
Mehalla gendarmerie at Franco's disposal to take over local garrisons, thus freeing the Regulares for service in Spain.

The hexagon also appears on the emblem of the 2nd Regulares Company of Tabor Rif II

Tabor (Regiment) Rif II was founded in 1911 by Lieutenant Colonel
Berenguer to fight in Africa.

The use of the six-pointed star is a peculiarity of these units. This
star appeared in the old Moroccan silver coins, stamps and documents,
and it was adopted to reflect the origin of the (formerly) Moroccan
native troops recruited for these units, mostly coming from the Rif
Mountains.

Image source: crwflags.com

This link provided by SJuan76 shows other emblems with hexagons.

SJuan76 has also commented that "A Moorish Guard (Guardia Mora) was kept for his [Franco's] personal security until the independence of Morocco" and has provided this additional link.

All translations from Google translate. All emphasis is mine.