When the ruling administrators, who are known as the kṣatriyas, turned astray from the path of the Absolute Truth, being desirous to suffer in hell, the Lord, in His incarnation as the sage Paraśurāma, uprooted those unwanted kings, who appeared as the thorns of the earth. Thus He thrice seven times uprooted the kṣatriyas with His keenly sharpened chopper.
The kṣatriyas, or the ruling administrators of any part of the universe, either on this planet or on other planets, are factually the representatives of the Almighty Personality of Godhead, and they are meant to lead the subjects towards the path of God realization. Every state and its administrators, regardless of the nature of the administration—monarchy or democracy, oligarchy or dictatorship or autocracy—have the prime responsibility to lead the citizens toward God realization. This is essential for all human beings, and it is the duty of the father, spiritual master, and ultimately the state to take up the responsibility of leading the citizens towards this end. The whole creation of material existence is made for this purpose, just to give a chance to the fallen souls who rebelled against the will of the Supreme Father and thus became conditioned by material nature. The force of material nature gradually leads one to a hellish condition of perpetual pains and miseries. Those going against the prescribed rules and regulations of conditional life are called brahmojjhita-pathas, or persons going against the path of the Absolute Truth, and they are liable to be punished. Lord Paraśurāma, the incarnation of the Personality of Godhead, appeared in such a state of worldly affairs and killed all the miscreant kings twenty-one times. Many kṣatriya kings fled from India to other parts of the world at that time, and according to the authority of the Mahābhārata, the kings of Egypt originally migrated from India because of Paraśurāma's program of chastisement. The kings or administrators are similarly chastised in all circumstances whenever they become godless and plan a godless civilization. That is the order of the Almighty.
(Srimad Bhagavatam-----2:7:22-----translation and purport).

Paraśurāma, or Reṇukāsuta: He is the son of Maharṣi Jamadagni and Śrīmatī Reṇukā. Thus he is also known as Reṇukāsuta. He is one of the powerful incarnations of God, and he killed the kṣatriya community as a whole twenty-one times. With the blood of the kṣatriyas he pleased the souls of his forefathers. Later on he underwent severe penances at the Mahendra Parvata. After taking the whole earth from the kṣatriyas, he gave it in charity to Kaśyapa Muni. Paraśurāma instructed the Dhanur-veda, or the science of fighting, to Droṇācārya because he happened to be a brāhmaṇa. He was present during the coronation of Mahārāja Yudhiṣṭhira, and he celebrated the function along with other great ṛṣis.
Paraśurāma is so old that he met both Rāma and Kṛṣṇa at different times. He fought with Rāma, but he accepted Kṛṣṇa as the Supreme Personality of Godhead. He also praised Arjuna when he saw him with Kṛṣṇa. When Bhīṣma refused to marry Ambā, who wanted him to become her husband, Ambā met Paraśurāma, and by her request only, he asked Bhīṣmadeva to accept her as his wife. Bhīṣma refused to obey his order, although he was one of the spiritual masters of Bhīṣmadeva. Paraśurāma fought with Bhīṣmadeva when Bhīṣma neglected his warning. Both of them fought very severely, and at last Paraśurāma was pleased with Bhīṣma and gave him the benediction of becoming the greatest fighter in the world.
(Srimad Bhagavatam-----1:9:6-7-----purport).

There are three Rāmas. One Rāma is Paraśurāma (Jāmadāgnya), another Rāma is Lord Rāmacandra, and a third Rāma is Lord Balarāma. In this verse the words rāmo'dri-kūṭeṣv atha indicate Lord Paraśurāma. The brother of Bharata Mahārāja and Lakṣmaṇa is Lord Rāmacandra.
(Srimad Bhagavatam-----6:8:15-----purport).

Lord Paraśurāma, being expert in killing the military strength of the enemy, worked with the speed of the mind and the wind, slicing his enemies with his chopper (paraśu). Wherever he went, the enemies fell, their legs, arms and shoulders being severed, their chariot drivers killed, and their carriers, the elephants and horses all annihilated.
In the beginning, when the army of the enemy was full of fighting soldiers, elephants and horses, Lord Paraśurāma proceeded into their midst at the speed of mind to kill them. When somewhat tired, he slowed down to the speed of wind and continued to kill the enemies vigorously. The speed of mind is greater than the speed of the wind.
(Srimad Bhagavatam-----9:15:31----translation and purport).

Paraśurāma is the Supreme Personality of Godhead, and his eternal mission is paritrāṇāya sādhūnāṁ vināśāya ca duṣkṛtām (B.G.4:8)—to protect the devotees and annihilate the miscreants. To kill all the sinful men is one among the tasks of the incarnation of Godhead. Lord Paraśurāma killed all the kṣatriyas twenty-one times consecutively because they were disobedient to the brahminical culture. That the kṣatriyas had killed his father was only a plea; the real fact is that because the kṣatriyas, the ruling class, had become polluted, their position was inauspicious. Brahminical culture is enjoined in the śāstra, especially in Bhagavad-gītā (cātur-varṇyaṁ mayā sṛṣṭaṁ guṇa-karma-vibhāgaśaḥ (B.G.4:13). According to the laws of nature, whether at the time of Paraśurāma or at the present, if the government becomes irresponsible and sinful, not caring for brahminical culture, there will certainly be an incarnation of God like Paraśurāma to create a devastation by fire, famine, pestilence or some other calamity. Whenever the government disrespects the supremacy of the Personality of Godhead and fails to protect the institution of varṇāśrama-dharma, it will certainly have to face such catastrophes as formerly brought about by Lord Paraśurāma.
(Srimad Bhagavatam-----9:16:18-19-----purport).

The Samanta-pañcaka pilgrimage site is celebrated because Lord Paraśurāma performed great sacrifices there after killing all the kṣatriyas in the world twenty-one times. When Lord Paraśurāma killed all the kṣatriyas, their accumulated blood flowed like a stream. Lord Paraśurāma dug five big lakes at Samanta-pañcaka and filled them with this blood. LordParaśurāma is viṣṇu-tattva. As stated in the Īśopaniṣad, viṣṇu-tattva cannot be contaminated by any sinful activity. Yet although Lord Paraśurāma is fully powerful and uncontaminated, in order to exhibit ideal character He performed great sacrifices at Samanta-pañcaka to atone for His so-called sinful killing of the kṣatriyas. By His example, Lord Paraśurāma established that the killing art, although sometimes necessary, is not good. Lord Paraśurāma considered Himself culpable for the sinful killing of the kṣatriyas; therefore, how much more culpable are we for such abominable unsanctioned acts. Thus, from time immemorial the killing of living entities is prohibited all over the world.
(Krsna Book).