Mars and Hercules

Mars and Hercules, the Greeks' Ares and Heracles, are profoundly linked  to each other.  Thus Pliny Natural History, Book 2, ch. VIII, §34 speaking of the planet that we now call that of Mars, has:

“... tertium Martis, quod quidam Herculis vocant, ...”.

“The third, of Mars, which some call of Hercules, ...”

Macrobius Saturnalia Book 3 chpt.12 §§5 to 8 (awend. Davies):

 “[5] Salios autem Herculi ubertate doctrinae altioris adsignat, quia is deus et apud pontifices idem qui et Mars habetur. [6] et sane ita Menippea Varronis adfirmat, quae inscribitur Ἄλλος  οὗτος Ἡρακλῆς, in qua, cum de Inuicto Hercule loqueretur, eundem esse ac Martem probauit. Chaldaei quoque stellam Herculis uocant, quam reliqui omnes Martis appellant. [7] est praeterea Octavii Hersennii liber, qui inscribitur de sacris Saliaribvs Tibvrtivm, in quo Salios Herculi institutos operari diebus certis et auspicato docet.[8] item Antonivs gnipho, uir doctus, cuius scholam Cicero post laborem fori frequentabat, Salios Herculi datos probat in eo uolumine, quo disputat quid sit festra, quod est ostium minusculum in sacrario, quo uerbo etiam Ennius usus est.”

“[5] As for the Salii, Vettius continued, in assigning them to  Hercules Vergil shows the wealth and depth of his learning, for the pontiffs too identify Hercules with Mars. [6]  And indeed this identification is supported by Varro’s Menippean satire This Other Hercules, in which the author, speaking of Hercules One of Many, has shown  that this god and Mars are one and the same.  The star, too, which is known to all other peoples as the Star of Mars is called by the Chaldeans the star of Hercules.  Furthermore, Octavius Hersennius, in his book entitled On the Rites of the Salii of Tibur, explains that the Salii were instituted for the service of Hercules and, after the taking of auspices, perform rites in his honour on certain fixed days. [8] Antonius Gnipho also, a learned man whose lectures Cicero used to attend when his work in court wasover, proves that the Sali were assigned to Hercules; the reference will be found in the roll in which the writer  discusses the meaning of the word festra (a small opening in a shrine), a word which has been used by Ennius too.”

Servius commentary on Vergil's Æneid 8.275 COMMUNEMQUE VOCATE DEUM and call on the common god... :

"... alii communem deum ideo dictum volunt, quia secundum pontificalem ritum idem est Hercules, qui et Mars: nam et stellam Chaldaeis dicentibus unam habere dicuntur, et novimus Martem communem dici: Cicero “Martemque communem”, Vergilius “et dis communibus aras” . item paulo post dat salios Herculi, quos Martis esse non dubium est.  ..."

"...Others wish the common gods to be called for the reason that after the priestly custom the same is Hercules who is Mars:  for it is said by the Chaldeans referring to the one star we know as of Mars to be called in common: ...  The same [Vergil] a little after gives the Salii to Hercules, who it is without doubt are Mars’.  ...".