Historical Background of the Valentine`s Day:

It actually all started with a little festival the Romans liked to hold every year, the festival of Lupercalia which was a fertility celebration, starting on February 13th and going through February 15th. During this festival, young women would put their names in an urn; young men would then draw names from the urn; whoever’s name they drew would then be their female companion for a year. This festival was celebrated annually for roughly 800 years.Eventually the Catholics came along and didn’t like this festival where young men and women draw lots to have as a sexual partner for a year. So the Catholics decided to replace it with a Catholic tradition.
In doing so, Pope Gelasius-I, in 496 AD, decided to replace the lot drawing part of the festival with his own lottery and celebrated his festival around the same time, February 14th. He proposed that instead of drawing young girl’s names from the urn, both boys and girls should draw saints names from the urn and for a year they would then strive to be like those saints. This didn’t go over well as it was a lot less fun than pulling names for primarily sexual purposes. Eventually, they went back to drawing girl’s names from the urns until the 16th century when the Roman Catholic Church once again decided to try to force the “Saint Valentine’s Day” down the Romans throats. The church pegged the festival to the legend of St. Valentine. Valentine’s Day name also came from Pope Gelasius-I. He proposed to make Saint Valentine the patron of the new celebration. The problem is there are actually Three St. Valentine's -- one a priest, one a bishop, and little is known about the third. In 469 A.D., Pope Gelasius declared Feb. 14 a day to honor St. Valentine, one of these three men.

Muslim Prespective:
It is not permissible for a Muslim to celebrate any of the festivals of the kuffaar, because festivals come under the heading of Shariah issues which are to be based on the sound texts.
“For every nation We have ordained religious ceremonies which they must follow” [al-Hajj22:67]
Participating in such festivals and other rituals is joining in with kufr, and joining in with some of its minor issues is joining in with some of the branches of kufr. Indeed, festivals are one of the most unique features that distinguish various religions and among their most famous symbols, so joining in with them is joining in with the most characteristic and famous symbols of kufr.
Prophet Muhammad ﷺ said: It is not permissible for the Muslims to imitate them in anything that is uniquely a part of their festivals, whether it is food, clothing, bathing, lighting fires, refraining from a regular habit, doing acts of worship or anything else. It is not permissible to give a feast or to give gifts, or to sell anything that will help them to do that for that purpose, or to allow children and others to play games that are part of the festivals, or to wear one’s adornments.
Al-Hafiz al-Dhahabi said: If the Christians have a festival, and the Jews have a festival, it is only for them, so no Muslim should join them in that, just as no Muslim should join them in their religion or their direction of prayer. [Tashabbuh al-Khasees bi Ahl al-Khamees, in Majallat al-Hikmah (4/193)]
Narrated that Anas (R.A.) said: When the Messenger ﷺ came to Madinah, they had two days when they would play. He ﷺ said: “What are these two days?” They said: “We used to play on these days during the Jaahiliyyah.” The Messenger ﷺ said: “Allaah has given you instead of them two days that are better than them: the day of al-Adha and the day of al-Fitr.” [This Hadith is classed as Saheeh by Al-Albaani in Saheeh Abu Dawood 1134]
This indicates that festivals are among the characteristics by which nations are distinguished, and it is not permissible to celebrate the festivals of the ignorant and the mushrikeen (polytheists).
Scholarly Fata’awas about Valentine’s Day Celebration.
Shaykh Ibn ‘Uthaymeen was asked:
In recent times the celebration of Valentine’s Day has become widespread among youth wherein they dress in red, and exchange red roses. We hope that you can explain the ruling on celebrating this festival, and what your advice is to Muslims with regard to such matters; may Allaah bless you and take care of you.
He replied:
Celebrating Valentine’s Day is not permissible for a number of reasons:
1- It is an innovated festival for which there is no basis in Islam.
2- It promotes love and infatuation.
3- It calls for hearts to be preoccupied with foolish matters that are opposing to the way of the righteous Salaf (may Allaah be pleased with them).
It is not permissible on this day to do any of the things that are characteristic of this festival, whether that has to do with food, drinks, clothing, exchanging gifts or anything else. The Muslim should be proud of his religion and should not be a weak character that follows every Tom, Dick and Harry. I ask Allaah to protect the Muslims from all temptations, visible and invisible, and to protect us and guide us. [Majmoo’ Fataawa al-Shaykh Ibn ‘Uthaymeen (16/199)]
The Standing Fiqh council was asked: Some people celebrate Valentine’s Day on the 14th of February every year. They exchange red roses, gifts and wear red clothes and congratulate one another. Some bakers make red colored sweets and draw hearts on them, and some stores advertise products that are especially for this day. 

What is your view on this?
They replied: The clear evidence of the Qur’an and Sunnah – and the agreement of the early generations of this Ummah – indicates that there are only two festivals in Islam: Eid al-Fitr and Eid al-Adha. Any other festivals that have to do with a person, a group, an event or anything else are innovated festivals, which it is not permissible for Muslims to observe, approve of or express joy on those occasions, or to help others to celebrate them in any way, because that is transgressing the sacred limits of Allaah, and whoever transgresses the sacred limits of Allaah has wronged himself. If the fabricated festival is also a festival of the kuffaar, then the sin is even greater, because this is imitating them and it is a kind of taking them as close friends, and Allaah has forbidden the believers to imitate them and take them as close friends in His Holy Book. And it is proven that the Prophet ﷺ said: “Whoever imitates a people is one of them.” Valentine’s Day comes under this heading because it is an idolatrous Christian festival, so it is not permissible for a Muslim who believes in Allaah and the Last Day to observe it or approve of it or congratulate people on it. Rather he has to ignore it and avoid it, in obedience to Allaah and His Messenger, ﷺ so as to keep away from the causes that invite the anger and punishment of Allaah. It is also haraam for the Muslim to help people to celebrate this or any other haraam festival by supplying any kind of food or drink, or buying or selling or manufacturing or giving or advertising etc., because all of that is cooperating in sin and transgression and is disobedience towards Allaah and His Messenger ﷺ Allaah says (explanation of the meaning):
“Help you one another in Al‑Birr and At‑Taqwa (virtue, righteousness and piety); but do not help one another in sin and transgression. And fear Allaah. Verily, Allaah is Severe in punishment” [al-Maa’idah 5:2]
Shaykh Ibn Jibreen Said: It is not permissible to sell these gifts and roses, if it is known that the purchaser celebrates these festivals or will give these things as gifts on those days, so that the seller will not be a partner of the one who does those innovations.

The Muslim must stick to the Book of Allaah and the Sunnah in all his affairs, especially at times of fitnah when evil is common. He should be smart and avoid falling into the misguidance of those who have earned Allaah’s anger and who have gone astray, and the evildoers who have no fear of Allaah and who do not have any pride in being Muslims. The Muslim must turn to Allaah and seek His guidance and remain dedicated in following it, for there is no Guide except Allaah and no one can make a person dedicated but Him. And Allaah is the source of strength. May Allaah send blessings and peace upon our Prophet Muhammad and his family and his companions.

Source: askislampedia.com