Part 1/2

In short, no, this site is likely run by an Islamic fundamentalist with a very negative view of other religions. Their "academic" section is full of half-sourced and cherry picked quotes with very little context or backing. The rest of the site doesn't appear much better. I would guess that the person who put the article up has never seen a Hindu, let alone looked into the doctrines and practices of Hinduism, contemporary or historical. In any case, lets get into what the Ashvamedha actually is.

"Aśvamedha" is generally translated as "Horse sacrifice" which is more or less the literal translation of the term. Going forward, what does that actually mean? The Indo-Aryans who composed the Ṛgvedā and Yajur Veda, in which the horse sacrifice is described, had a culture that revolved around horses and cattle. As nomadic pastoralists, these two creatures were vital to their economy, which revolved around trading, especially in horses, and raiding. It is likely that they supplied horses to the major cultures of the Middle East, such as Sumer, Akkad, and Elam as well as trading with and occasionally warring with each other and neighboring peoples, such as the proto-Finno-Urgic people and the pre-Indo-Europeans in East Europe. Perhaps because of the prestige associated with horses and there significance to their economy and culture, horses acquired a religious significance and were present in large burial sites often with other animals of prestige and signs of wealth, such as bone decorations and bronzeware. These sacrifices were common among all Indo-European peoples, from the Celts to the Scythians to the Indo-Aryans. Early horse sacrifices are primarily associated with burial sites, but by the time of the middle period, when peoples like the proto-Latins and proto-Celts broke off and entered Europe proper, the sacrifice had become much more complicated. It should be noted, that while I am not aware of a large amount of Proto-Indo-European horse sacrifice remains outside of burials, this does not mean they didn't exist, rather, an absence of evidence here is not evidence of absence. However, in this later period, we certainly find evidence of more complicated sacrificial rituals associated with cattle and horses, with some having their own special graves and marks of ritual dismemberment.

By the time the Indo-Aryans moved into India, they had absorbed rituals from the surrounding peoples and began to codify their ritual texts in the form of oral recitations, preserved today in the Vedas. The Vedas are an interesting collection of materials, ranging from poems, to hymns, to ritual instructions, to myths. The horse sacrifice is first mentioned in the Ṛgvedā within the context of a ritual beheading of a horse and gifting the head in an invocation and deed recitation of the Aśvins, who were physician gods as wells as part horse themselves. The 162 hymn of the Ṛgveda's first maṇḍala gives, in fairly bloody detail, the horse sacrifice:

Mitra, Varuṇa, Aryaman the Active, Indra the ruler of the Ṛbhus, and the Maruts - Let them not fail to heed us when we proclaim in the assembly the heroic deeds of the racehorse who was born of the gods. When they lead the firmly grapsed offering in front of the horse that is covered with cloths and heirlooms, the dappled goat goes bleating straight to the dear dwelling of Indra and Pūṣan. This goat for the gods is led forward with the horse as the share for Pūṣan...When, as the ritual law ordains, the men circle three times, leading the horse that is to be the oblation on the path to the gods, the goat who is the share for Pūṣan goes first, announcing the sacrifice to the gods...The hewers of the sacrificial stake, and those who carve the knob for the horses sacrificial stake, and those who gather together the things to cook the charger - let there aproval encourage us. The horse with his smooth back went forth into the fields of the gods, just when I made my prayer...We have made him a welcome companion at the banquet of the gods. The charges's rope and halter, the reins and bridle on his head, and even the grass that has been brought up to his mouth - let all of that stay with you, even among the gods. Whatever runs off your body when it has been placed on the spit and roasted by the fire, let it not lie there on the earth or on the grass, but given to the gods who long for it... The cloth that they spread beneath the horse, the upper covering, the golden trappings on him, the halter and the fetters on his feet - let these things that are his own bind the horse among the gods...The axe cuts through the thirty-four ribs of the racehorse who is the companion of the gods. Keep the limbs undamaged and place them in the proper pattern. Cut them apart, calling out piece by piece... Let not your dear soul burn you as you go away. Let not the axe do lasting harm to your body. Let no greedy, clumsy slaughterer hack in the wrong place and damage your limbs with his knife. You do not really die through this, nor are you harmed. You go to the gods on paths pleasant to go on. The two bay stallions, the two roan mares are now your chariot mates...Let this racehorse bring us good cattle and good horses, male children, and all-nourishing wealth. Let Aditi make us free from sin. Let the horse with our offerings achieve sovereign power for us.

Okay, so there is clearly a lot to unpack here. Aside from the grisly details of the actual process of the sacrifice, there is quite a bit of figurative language and mythological background to this sacrifice. Notably absent is any beheading, as in later traditions and the Ṛgvedic hymn to the Aśvins, rather, the horse is staked and then stripped of flesh which is then cooked, notably leaving the limbs intact. There is an immense degree of respect given to the horse during the process, while it is a sacrifice to feed the gods (humans would never partake in the cooked meat, rather they would offer it to fire or bury it), its spirit is set free to roam in the heavens. The horse is both the subject and the receiver of the sacrifice in some ways, as it is given prosperity in heaven but its bodily form is given to the gods as a magnificent feast, too sacred for humans to partake in. The horse is furthermore given the utmost respect during the sacrifice and is dressed in finery during it, later accounts and depictions would have it painted with holy paints and sandalwood paste. It is also notably that not only is the next hymn directly in praise of a horse but that perhaps the largest section of the Yajurveda describes the hymns and oblations to be done before and during the sacrifice. While this may seem barbaric to the modern reader, we have to understand that this was a ritual done with the utmost respect and in many ways love by those who conducted it. It was a dignified process.

We can also see that this was not a garden variety sacrifice, so much so that later it was only preformed by powerful kings, those who would later use titles like Mahārāja adi Rāja (Great king of kings, similar to Shahanshah in Persia) and owned vast swaths of land. This sacrifice early on was done for the whole community and on rare occasions, yearly at most but probably not even that frequently. Later on, tradition would say that it could be done every decade or century and it would come to legitimize a king's rule and grant prosperity for the whole of the kingdom.

In these later contexts, the ritual would evolve and shift in emphasis. I've already mentioned that the sacrificer must be a powerful king, but by the time we begin to see inscriptions and depictions referencing it (coinciding with a Hindu revival around the 2nd century CE) it had become a grand affair where the horse would be paraded through the whole kingdom and then sacrificed with an even larger number of other animals than those specified in the Yajurveda. The emphasis moved from a ritual of fertility and fecundity for the people and land, to one that cemented the king's and kingdom's status and power.

This shift was gradual, and happened for a number of reasons. The people of the Ṛgveda and to a much lesser extent the Yajurveda were pastoral nomads, and horses held not only prestige but intrinsic value, wealth was measured not in gold or land, but horses and cattle so to sacrifice a horse meant a large commitment. By the late Vedic period, the Indo-Aryans had begun to settle and move from that semi-nomadic pastoral lifestyle, to a sedentary and urbanized one. This led to a decline in the value of horses as they were no longer essential, but an item of prestige for the elite, furthermore, the surplus of food allowed populations of humans AND horses to grow. We also see the relative status of cattle begin to rise as they were comparatively easy to keep and maintain as well as providing milk and butter.