Why was Avshalom riding a donkey into battle?

Question

In the battle between Avshalom's army and David's forces Avshalom is riding a donkey which runs away when Avshalom is caught by his hair in a tree.

וַיִּקָּרֵא אַבְשָׁלוֹם לִפְנֵי עַבְדֵי דָוִד וְאַבְשָׁלוֹם רֹכֵב עַל־הַפֶּרֶד וַיָּבֹא הַפֶּרֶד תַּחַת שׂוֹבֶךְ הָאֵלָה הַגְּדוֹלָה וַיֶּחֱזַק רֹאשׁוֹ בָאֵלָה וַיֻּתַּן בֵּין הַשָּׁמַיִם וּבֵין הָאָרֶץ וְהַפֶּרֶד אֲשֶׁר־תַּחְתָּיו עָבָר׃

Absalom encountered some of David’s followers. Absalom was riding on a mule, and as the mule passed under the tangled branches of a great terebinth, his hair got caught in the terebinth; he was held between heaven and earth as the mule under him kept going. (2 Shmuel 18:9)

Yet we know that Avshalom had a chariot

וַיְהִי מֵאַחֲרֵי כֵן וַיַּעַשׂ לוֹ אַבְשָׁלוֹם מֶרְכָּבָה וְסֻסִים וַחֲמִשִּׁים אִישׁ רָצִים לְפָנָיו׃

Sometime afterward, Absalom provided himself with a chariot, horses, and fifty outrunners. (ibid 15:1)

A chariot would seem to be a better transport for a (would-be) king during a battle, rather than a mule. Why then did Avshalom opt to ride a donkey into battle instead of a chariot?

Please provide answers that are either based in the text and/or sourced rather than personal speculation (eg he knew a donkey would be better for a battle in the forest 18:6 precludes that)

Answer 1

In I Melachim 1:33 David commands that Shlomo ride to be anointed on “the mule which is mine”, in response to Adoniyahu claiming the kingship for himself. Evidently, the mule was deemed as fitting for royalty as the horse.

Interestingly, Abarbenel states that horses symbolize war, whereas the mule represents peace. Thus Shlomo was ridden on a mule to symbolize a peaceful reign, while Adoniyahu rode on horseback (ibid 1:5).

Answer 2

The verses use the word "פרד" which means mule. There's some evidence that mules were used in ancient times both as mounts for important people and as war steeds and even chariot-animals. See here for example. According to the article in the link, the advantage of the ancient mule was that it could sometimes be bred to be significantly taller (and thus, more prominent and imposing) than the average horse:

"...There is also speculation, however, that the Hittites used mules earlier than the Third Century as riding animals for war leaders and standard bearers [...]. This was because the hybrid vigour of the ass-horse cross resulted in animals that at 14 hands high (142 cm) were possibly more than one hand (10 cm) taller than the local horse and therefore generals and standard bearers could be more easily seen by the troops."

Another advantage was stated by Virginia Miller:

"Mules would have been a better choice for this battle as their dietary needs are easier to meet, and they are more surefooted than horses on uneven terrain. The terrain was known to be difficult as it is stated that the forest claimed more lives than the sword did (18:8). It might also be said that Auld’s observation that the princes fled from Amnon’s assassination on mules re-enforces the idea that mules were thought to be special animals fit for royalty."

Furthermore, given that Avshalom made a chariot for a royal procession seems to show that the chariot was not a key component of the Israelite military. His chariot may have been more clunkier and not as streamlined as a war chariot.

More symbolically, Rabbi Eliezer Kashtiel suggested in this class [in Hebrew] that the mule, called 'pered' in Hebrew, symbolizes the split of the kingdom (pirud - פירוד) caused by Avshalom.