Unlike any other national flag, the National Flag of Nepal is non-quadrilateral in shape but has two single pennons, the vexillological word for a pennant. The flag consists of two juxtaposed triangular figures whose base color is crimson (#DC143C) and whose borders are deep-blue (#003893), the white (#FFFFFF) emblem of the "Crescent Moon" with eight rays out of sixteen centers the top pennon while the bottom one has a white (#FFFFFF) emblem of a twelve rayed sun. There are no written shreds of evidence as to who first designed the triangular Nepali Flag but  Shankar Nath Rimal, a civil engineer standardized the flag at King Mahendra's behest. And on 16 December 1962 "The National flag of Nepal" was adopted and institutionalized as a state and civil flag of this sovereign country. Featured photo  of Nepali Flag adapted from Timilsina Bimal Two Gorkhali figurines hoisting Nepal’s National Flag in front of Sindhuli Gadhi War Museum. Sindhuli District. Photo by Nikki Thapa

The Colours & Shape of the Nepali Flag

Crimson Red is the national color of Nepal that indicates the blood of the brave spirits of the Nepalese people. It is also the color of the Rhododendron (the national flower of Nepal) and a sign of victory in war. The Deep Blue border of the flag symbolizes the peace and harmony that has been prevalent in the country. And with that Late King Birendra at his farewell address on February 25 1975 to the foreign dignitaries assembled in Kathmandu to attend his Royal Coronation proposed to declare Nepal as a "Zone of Peace".  The proposal has been endorsed by over 130 nations except for India. The two pennons or triangles of the Nepali Flag simultaneously symbolize the Himalayas and "Hinduism and Buddhism" the two major religions that have co-existed for thousands of years.  Some elucidate that the flag's triangle shape means a Nepalese pagoda because when a mirror positioned at the hoist side of the flag it generates an image of a pagoda. Nepal was the one and only Hindu Kingdom for a long period of time (until 2008), and a triangular flag is the trace of Hinduism.  Another additional characteristic of the triangular-shaped flag is due to its compact-size the flag can easily furl and be visible from distance. The emblems of the moon and sun in the hopes that Nepal will last as long as these two celestial bodies. The moon symbolizes the serenity of Nepalese whereas the sun symbolizes fierce resolve. The moon represents the shades and the cool weather of the high Himalayan region of the country i.e. 8848m. whereas the sun represents the heat and the high temperature of Southern Nepal's plains,  just 64m. above sea level. And recent research has shown that the National Flag of Nepal is the most mathematical flag in the world. https://www.youtube.com/watch?v=f2Gne3UHKHs

History of Nepali Flag

Hundreds of independent states that existed between the 17th to 19th centuries on the Indian subcontinent prior to the British Invasion had state triangular flags of their own representing the ruling dynasty. Many of them after colonization or getting their independence back modified their flags' designs, shapes, and colors to meet European standards. But Nepal remained the only separate and sovereign kingdom that was never officially colonized by the British. She has proudly flown the traditional flag that has evolved through the years but not once changed its triangular design. List of flags of Nepal. Images from Wikipedia.

Rato Ra Chandra Surya, Jangi Nishan Hamro..

The trio Phatteman Rajbhandari (singer), Ambar Gurung (musician), and Gopal Prasad Rimal (lyricist) released a song "रातो र चन्द्र सूर्य जङ्गी निशान हाम्रो... (Rato Ra Chandra Surya") mentioning the national flag of Nepal as an opening line of the song.  Rimal wrote the song when autrocratic Ranas were still ruling the country. This patriotic song calls on the unyielding spirit of the Nepalese' bravery, resiliency and  honour.  It was later reprised by the band called 1974 AD in 2015 and then in 2019 the band Nepathaya on its 25th anniversary.

रातो र चन्द्र सूर्य जङ्गी निशान हाम्रो  
जिउँदो रगतसरी यो बल्दो यो शान हाम्रो  

हिमालझैँ अटल यो झुकेन यो कहिल्यै 
लत्रेन यो कहिल्यै जङ्गी निशान हाम्रो 

यो जन्मिँदै जगतमा कैयौं प्रहार आए 
साम्राज्य दुई हारे हारेन शान हाम्रो 

जबसम्म चन्द्र सूर्य आकाशमा रहन्छ 
तबसम्म हुन्छ आफ्नै रातो रगत यो हाम्रो 

गाईसरी छन् साधु जोजो यहाँ जगतमा  
सबको शरण बलियो जङ्गी निशान हाम्रो  

रातो र चन्द्र सूर्य जङ्गी निशान हाम्रो 
जिउँदो रगतसरी यो बल्दो यो शान हाम्रो

Rato ra chandra surya jangi nishan hamro
jiudo ragat sari yo baldo yo saan hamro

himal jhai atal yo jhukena yo kahile
latrena yo kahile jangi nishan haamro
yo janmadai jagatma kaiyau prahar aaye
samrajye duri hare, harena shaan hamro

Rato ra chandra surya jangi nishan hamro
jiudo ragat sari yo baldo yo saan hamro

jabasamma chandra surya aakashma rahancha
taba samma huncha aafnai rato ragat yo hamro
gai sari chan sadhu jo jo yaha jagatma
sabako saran baliyo jangi nishan hamro

Rato ra chandra surya jangi nishan hamro
jiudo ragat sari yo baldo yo saan hamro