I do so love it when my handle is topical in this subreddit. If you want a TL;DR before we get started, it's "not exactly". But I see this as an excellent segue into discussing the nature of sacrifice in the Andes, as in later years they were performed specifically for the appeasement of mountain spirits and volcanoes, in a ceremony called the qhapaqocha. This ceremony was an immense display of Inca imperial ideology, writ large across their environment. So while I noticed (in the course of writing this) that others have mentioned the Andes in answering this question, I'm here to explain a little about why Andeans felt it necessary to give their most beautiful children to their mountains.

The Motive for Sacrifice: Caring for the Apu

In the Pre-Contact Andes, volcanoes were active agents of the landscape. The Andes are still being uplifted as the Nazca plate moves underneath the South American plate; this has led to the existence of many active volcanoes in the region. Mountains, and by extension volcanoes, were considered apu, the sacred ancestors of all Andean people, for millennia. The story told by the Inca goes that Wiraqocha, the Creator, sent out all people of the Andes from the navel of the universe, Lake Titicaca, through underground aquifers to be birthed at their respective homelands through their apu's springs and caves. From there Wiraqocha traveled northwest between the two chains of the Andes (some versions have two disciples that each took one of the outer paths astride the two chains) and helped each community learn to farm their land and learn their traditions. Thus while Wiraqocha was important to every community, each community's named apu was their oldest, most cherished ancestor, providing the water for their crops, the fertile soil to till, the vicuñas (wild camelids) to hunt.

Volcanoes were occasionally, though not always, a community's apu; however they demanded similar respect to any other mountain. At the town of Raqch'i, Bill Sillar of the University College of London told me and a group of students a story, which came down from the chronicler Juan de Betanzos:

Viracocha came to a province that the Inka call Cacha, which belongs to the Canas Indians. When he called the Indians in this area into being they came out armed, and because they did not know who Viracocha was they came at him with their weapons ready to kill him. When he saw that these Indians were coming to attack him, Viracocha instantly caused fire to fall from heaven, burning a range of mountains near the Indians. When the Canas Indians saw the fire, they feared they would be burned. Throw­ing their weapons to the ground, they went straight to Viracocha and pros­trated themselves before him. When Viracocha saw them thus, he took a staff in his hand and went to where the fire was. He gave it two or three blows with his staff, which put it completely out, whereupon he told the Indians that he was their maker. The Canas Indians built a sumptuous "huaca", which means a shrine or idol, at the place where Viracocha stood when he called the fire from heaven and from which he went to put it out. In this huaca they and their descendants offered a great quantity of gold and silver. In memory of Vira­cocha, and of what had taken place there, the Canas Indians set a stone statue up in the huaca.

The volcano adjacent to the town has been dormant ever since then, and even today remnants of the Temple of Wiraqocha still stand in Raqch'i, built by the Inca in support of, or perhaps due to, the stories surrounding this town and its volcano. A sizable Wari occupation in the area dating to the Middle Horizon, some eight or nine hundred years before the Inca, suggest that knowledge of the importance of this site could have been understood long before the Inca existed. However, the supplication of mountain spirits in the Andes was expanded greatly by the Incas, in a cleverly executed and legitimizing series of rituals known as the qhapaqocha.

The "Powerful Obligation"

Before getting into the nitty-gritty of the actual acts of sacrifice, it should be noted that some of the rationale of human sacrifice is not as clear for the Inca as it is for, say, Mesoamerica. D'Altroy notes that in those cultures sacrifice was seen as repayment to the gods for having been given life; sacrifice was fulfilling a reciprocal arrangement. This is not the case for the Inca, who seemingly preferred that the best people of the Andes had a right to join the Sun, the Thunder, and the Creator.

Reserved for the most important acts within Tawantinsuyu, the qhapaqocha ceremonial suite performed several functions within the Inca Empire. With large events such as the rise or death of the emperor, or a major military victory, the most beautiful children of communities across the Empire were curried from their homes and brought to Cuzco, the capital of the empire and the center of the Inca universe. (Alternately, and usually for military-oriented purposes, prisoners of war could be be used for this.) Molina, as described by D'Altroy, illustrated one of these ceremonies in the context of the ascension of an emperor. One boy and one girl of roughly ten years were requested of all communities, and brought to the capital along with offerings of camelids, fine textiles, and figurines of gold, silver, and shell. Once in the capital, the children were paired off and symbolically married. These couples, dressed in fine cloth, were paraded around the town square; some of them were strangled, and some had their hearts torn out of their chests. The remaining children were then involved in one of the more incredible acts of the ritual: priests traveled in a retinue with a few children, sometimes in straight-line paths away from the center, which have been postulated to synch up with the ceque system of huacas centered in Cuzco. Along their paths they interred figurines of silver and gold, with more children being sacrificed to the most sacred places, which were often apu. This extended to the very frontiers of the Inca realm. Archaeological studies by Johan Reinhard and others have shown that volcanoes were not exempt from these ceremonies; children, once taken up the mountain, were interred while still alive (though often unconscious from head blows or heavily intoxicated with chicha corn beer) along with some of the aforementioned figurines.

In this way, the Inca incorporated and accepted local ideologies and ancestors as sacred; however they also legitimized their control over these sacred landscapes through limiting access and supplicating these mountain ancestor spirits. This placed the Inca as interlocutors and arbiters of communities' own ancestors, taking them as respectful hostages to their will.

• Sillar, Bill (1999). Pilgrims past and present: the ritual landscape of Raqchi, southern Peru. Archaeology International 3:49-52.
• D'Altroy, Terence (2002). The Incas. Blackwell Publishing.

There is no record of any ancient cultures ritually throwing victims into volcanos. In fact it is very unlikely it even could have happened as it takes a lot of modern gear just to get to near the top of an active volcano.

Ritual killings of a human have taken place throughout history. Usually by burning, mutilation (including strangulation, crushing, and cutting), or drowning. The Mayans are noted for cutting the hearts out of their sacrifice.

Humans most likely have been sacrificed ON volcanos, but not by tossing them into the vent:

Virgins have been sacrificed on, if not in, volcanoes. I’ll go out on a limb and say this is 100 percent true. The mummified remains of numerous murdered Incan children, many of them female, have been found on the upper slopes of volcanoes in the Andes. For example, a girl was discovered on Mount Ampato in Peru in 1995 and two girls and a boy on Llullaillaco in Argentina in 1999. The victims, aged six to adulthood, were well dressed and nourished, suggesting they’d been fattened for the slaughter. I don’t know if on examination any of the children were found to be virgins but will politely assume they were.

Tossing victims(be they children/virgins/pure/etc) into an active volcano is just a Hollywood fantasy.

Throughout history many cultures have talked about the power of volcanoes but I don't think I've actually heard about ritual sacrifice being performed on them. In general, ritual sacrifice is a public spectacle in which a higher class (elites or religious class) solidifies their status onto their peers by displaying their connection to a higher power. In other words, they can kill people because they claim they are connected to the gods somehow and by killing someone they can apiece the gods while also solidifying their status within their society. Many cultures have practiced ritual sacrifice like Mayans or Aztecs, but their goal was to show it to people. Throwing them into a volcano would not be ideal because no one would see them do it. However, Instead of throwing them to a volcano, Mayans did sacrifice people onto cenotes, pools of landlocked water. But this was performed in accordance to their beliefs that caves and water features had a key role in helping people. Having said that, I don't think it would be entirely out of the real of possibility that some cultures practiced throwing people onto volcanoes. If that happened, it could probably happen on smaller tribe-like cultures on Oceania or somewhere where volcanoes are prominent in a culture. That's where my instinct would tell me to look for. But this raises another interesting issue. I am an archaeologist, and as such, how will I be able to find evidence of such behaviour? I don't think any remains thrown into a volcano would survive.

Just as a follow-up question - with this sort of topic, is it possible to give a really solid answer if there is no source that says "there is no evidence of this?" This isn't my field at all, so I'm really curious about how this sort of question is answered. Is a better response one that examines where such a stereotype may have come from (as in, "no one ever claimed to witness this, but it was first described in an Edgar Rice Burroughs story from 1917," or something along those lines)?

At Mt. Bromo, East Java, Indonesia. There is a tradition called Kasada, in which the Tengger Tribe once a year, will sacrifice some of the harvest in that year, to be thrown at Mt. Bromo Crater.

This tradition is based on a legend that a Prince name Joko Seger and his wife Roro Anteng are having fertility problem. They pray to the gods for having a child. The Gods agree on one condition, that they will sacrifice their last child to the Gods. They eventually have 24 children. When the 25th child is born, the Gods ask them that they want her as the sacrifice. At first the couple try to negotiate with the Gods, because they love her very much more then the others.

However after considering that they have already given a bless for having children, they eventually agreed and sacrifice her.

The tradition itself is still an annual event in Mt. Bromo, the tengger tribe will gather up resource from harvest, and bring it to the top of Mt. Bromo and throw it at the crater.

It is not known whether there was a human sacrifice during the Kasada rituals in the past.

I'm really sorry that i don't have the written resource in English, however this story can be found in Indonesia Folktales book, written in Bahasa.